The Ring programming language version 1.5 book - Part 6 of 31

Ring Documentation, Release 1.5
x=10 y=20
test()
func test
see isglobal("x") + nl +
isglobal("y") + nl +
isglobal("z") + nl
Output:
1
1
0
42.7 isfunction() Function
We can check if a Ring function is deﬁned or not using the isfunction() function.
Syntax:
isfunction(cFunctionName) --> returns 1 if the Ring function is defined
returns 0 if the Ring function is not defined
Example:
see isfunction("f1") + nl +
isfunction("f2") + nl +
isfunction("f3") + nl
func f1
see "message from f1()" + nl
func f2
Output:
1
1
0
42.8 iscfunction() Function
We can check if a C function is deﬁned or not using the iscfunction() function.
Syntax:
iscfunction(cFunctionName) --> returns 1 if the C function is defined
returns 0 if the C function is not defined
Example:
see iscfunction("len") + nl +
iscfunction("add") + nl +
iscfunction("test") + nl
42.7. isfunction() Function 270

Output:
1
1
0
42.9 packages() Function
We can get a list of packages names using the packages() function.
Syntax:
packages() --> a list contains packages names
Example:
See packages()
Package Package1
Class class1
Func f1
Package Package2
Class class1
Func f1
Package Package3
Class class1
Func f1
Package Package4
Class class1
Func f1
Output:
package1
package2
package3
package4
42.10 ispackage() Function
We can check if a package is deﬁned or not using the ispackage() function.
Syntax:
ispackage(cPackageName) --> returns 1 if the Package is defined
returns 0 if the Package is not defined
Example:
See ispackage("package1") + nl +
ispackage("package4") + nl +
ispackage("package5") + nl +
ispackage("package3") + nl
42.9. packages() Function 271

Package Package1
Class class1
Func f1
Package Package2
Class class1
Func f1
Package Package3
Class class1
Func f1
Package Package4
Class class1
Func f1
Output:
1
1
0
1
42.11 classes() Function
We can get a list of classes names using the classes() function.
Syntax:
classes() --> a list contains classes names
Example:
See classes()
Class class1
Func f1
Class class2
Func f1
Class class3
Func f1
Output:
class1
class2
class3
42.12 isclass() Function
We can check if a class is deﬁned or not using the isclass() function.
Syntax:
42.11. classes() Function 272

isclass(cClassName) --> returns 1 if the Class is defined
returns 0 if the Class is not defined
Example:
see isclass("class4") + nl +
isclass("class3") + nl +
isclass("class2") + nl
Class class1
func f1
class class2
func f1
class class3
func f1
Output:
0
1
1
42.13 packageclasses() Function
We can get a list of classes names inside a package using the packageclasses() function.
Syntax:
packageclasses(cPackageName) --> a list contains classes names inside the package
Example:
see "classes in Package1" + nl
see packageclasses("Package1")
see "classes in Package2" + nl
see packageclasses("Package2")
Package Package1
Class class1
Func f1
Package Package2
Class class1
Func f1
Class class2
Func f1
Class class3
func f1
Output:
classes in Package1
class1
classes in Package2
class1
42.13. packageclasses() Function 273

class2
class3
42.14 ispackageclass() Function
We can check if a class is deﬁned inside package or not using the ispackageclass() function.
Syntax:
ispackageclass(cPackageName,cClassName) --> returns 1 if the Class is defined
returns 0 if the Class is not defined
Example:
see ispackageclass("package1","class1") + nl +
ispackageclass("package1","class2") + nl +
ispackageclass("package2","class1") + nl +
ispackageclass("package2","class2") + nl
Package Package1
Class class1
Func f1
Package Package2
Class class1
Func f1
Class class2
Func f1
Class class3
func f1
Output:
1
0
1
1
42.15 classname() Function
We can know the class name of an object using the classname() function
Syntax:
classname(object) --> Returns the object class name
Example:
o1 = new point
o2 = new rect
see classname(o1) + nl # print point
see classname(o2) + nl # print rect
class point
class rect
42.14. ispackageclass() Function 274

42.16 objectid() Function
We can know the object id using the objectid() function
Syntax:
objectid(object) --> Returns the object id
Example:
o1 = new point
see objectid(o1) + nl
test(o1)
func test v
see objectid(v) + nl
Class point x y z
Output:
021B5808
021B5808
42.17 isobject() Function
We can check the variable to know if it’s an object or not using the isobject() function
Syntax:
isobject(variable) --> Returns True if it's an object, False if it's not
42.18 attributes() Function
We can get the object attributes using the attributes() function
Syntax:
attributes(object) --> Returns a list contains the object attributes
Example:
o1 = new point
aList = attributes(o1) # we can use see attributes(o1)
for t in aList see t next # print xyz
Class Point x y z
42.19 methods() Function
We can get the object methods using the methods() function
Syntax:
42.16. objectid() Function 275

methods(object) --> Returns a list contains the object methods
Example:
o1 = new test
aList = methods(o1)
for x in aList
cCode = "o1."+x+"()"
eval(cCode)
next
Class Test
func f1
see "hello from f1" + nl
func f2
func f3
func f4
Output:
hello from f1
hello from f2
hello from f3
hello from f4
42.20 isattribute() Function
We can test if the object contains an attribute or not using the isattribute() function
Syntax:
isattribute(object,cAttributeName) --> Returns True if the object contains the attribute
Example:
o1 = new point
see isattribute(o1,"x") + nl # print 1
see isattribute(o1,"t") + nl # print 0
see isattribute(o1,"y") + nl # print 1
see isattribute(o1,"z") + nl # print 1
class point x y z
42.21 isprivateattribute() Function
We can test if the object contains a private attribute or not using the isprivateattribute() function
Syntax:
42.20. isattribute() Function 276

isprivateattribute(object,cAttributeName) --> Returns True if the object
contains the private attribute
Example:
o1 = new person
see isprivateattribute(o1,"name") + nl +
isprivateattribute(o1,"address") + nl +
isprivateattribute(o1,"phone") + nl +
isprivateattribute(o1,"job") + nl +
isprivateattribute(o1,"salary")
Class Person
name address phone
private
job salary
Output:
0
0
0
1
1
42.22 ismethod() Function
We can test if the object class contains a method or not using the ismethod() function
Syntax:
ismethod(object,cMethodName) --> Returns True if the object class contains the method
Example:
o1 = new point
see ismethod(o1,"print") + nl # print 1
mylist = []
mylist + new point
see ismethod(mylist[1],"print") + nl # print 1
class point x y z
func print
see x + nl + y + nl + z + nl
42.23 isprivatemethod() Function
We can test if the object class contains a private method or not using the isprivatemethod() function
Syntax:
42.22. ismethod() Function 277

isprivatemethod(object,cMethodName) --> Returns True if the object class contains
the private method
Example:
o1 = new Test
see isprivatemethod(o1,"f1") + nl +
isprivatemethod(o1,"f2")
Class Test
func f1
private
func f2
Output:
0
1
42.24 addattribute() Function
We can add an attribute (or a group of attributes) to the object state (not the class) using the addattribute() function
Syntax:
AddAttribute(object,cAttributeName|aAttributesList)
Example(1):
see new point {x=10 y=20 z=30}
Class Point
AddAttribute(self,["x","y","z"])
Example(2):
o1 = new point
addattribute(o1,"x")
addattribute(o1,"y")
addattribute(o1,"z")
see o1 {x=10 y=20 z=30}
class point
Output:
x: 10.000000
y: 20.000000
z: 30.000000
42.25 addmethod() Function
We can add a method to the object class using the addmethod() function This method can be used with any object from
the same class.
42.24. addattribute() Function 278

Syntax:
AddMethod(Object,cNewMethodName,cMethodName|AnonymousFunction)
Example:
o1 = new point { x=10 y=20 z=30 }
addmethod(o1,"print", func { see x + nl + y + nl + z + nl } )
o1.print()
Class point
x y z
Output:
10
20
30
Instead of using anonymous function to add new method to the class, we can use the function name
Example:
o1 = new point { x=10 y=20 z=30 }
myfunc = func { see x + nl + y + nl + z + nl }
addmethod(o1,"print", myfunc )
addmethod(o1,"display", myfunc )
addmethod(o1,"show", myfunc )
o1.print()
o1.display()
o1.show()
Class point
x y z
Output:
10
20
30
10
20
30
10
20
30
Since we add the method to the class, any object from that class can use this method
Example:
o1 = new point { x=10 y=20 z=30 }
o2 = new point { x=100 y=200 z=300 }
o3 = new point { x=50 y=150 z=250 }
addmethod(o1,"print", func { see x + nl + y + nl + z + nl } )
42.25. addmethod() Function 279

o1.print()
o2.print()
o3.print()
Class point
x y z
Output:
10
20
30
100
200
300
50
150
250
42.26 getattribute() function
We can get the object attribute value using the getattribute() function
Syntax:
GetAttribute(oObject,cAttributeName) ---> Attribute Value
Example:
o1 = new point
see getattribute(o1,"name") + nl +
getattribute(o1,"x") + nl +
getattribute(o1,"y") + nl +
getattribute(o1,"z") + nl
Class Point
x=10 y=20 z=30
name = "3D-Point"
Output:
3D-Point
10
20
30
Example:
We can Find a Class List Member using GetAttribute() using a function ﬁndclass() The Find uses the member name,
rather than the column number
myList =
[new Company {position=3 name="Mahmoud" symbol="MHD"},
new Company {position=2 name="Bert" symbol="BRT"},
new Company {position=1 name="Ring" symbol="RNG"}
]
42.26. getattribute() function 280

see myList
see nl +"=====================" + nl + nl
for i = 1 to len(myList)
see "Pos: "+ i +" | "+ myList[i].position +" | "+ myList[i].name +
" | "+ myList[i].symbol +" | "+ nl
next
See findclass(myList, "MHD", "symbol") +nl ### Specify Member class name
###---------------------------------------
func findclass classList, cValue, classMember
See nl + "FindClass: " +" "+ cValue + nl + nl
for i = 1 to len(classList)
result = getattribute( classList[i], classMember )
See "Result-Attr: " + i +" "+ result +nl
if result = cValue
j = i
ok
next
return j
###--------------------------------------
class company position name symbol
Output:
Pos: 1 | 3 | Mahmoud | MHD |
Pos: 2 | 2 | Bert | BRT |
Pos: 3 | 1 | Ring | RNG |
FindClass: MHD
Result-Attr: 1 MHD
Result-Attr: 2 BRT
Result-Attr: 3 RNG
1
42.27 setattribute() function
We can set the object attribute value using the setattribute() function
Syntax:
SetAttribute(oObject,cAttributeName,Value)
Example:
o1 = new person
setattribute(o1,"cName","Mahmoud")
42.27. setattribute() function 281

setattribute(o1,"nSalary",1000000)
setattribute(o1,"aColors",["white","blue","yellow"])
see o1
see o1.aColors
Class Person
cName
nSalary
aColors
Output:
cname: Mahmoud
nsalary: 1000000.000000
acolors: List...
white
blue
yellow
42.28 mergemethods() Function
We can share methods between classes without inheritance using the MergeMethods() function
This function merge class methods to another class.
Syntax:
MergeMethods(cClassNameDestination,cClassNameSource)
Example:
mergemethods("count","share")
mergemethods("count2","share")
o1 = new count { test() }
o1 = new count2 { test() }
Class Share
func one
see "one" + nl
func two
see "two" + nl
func three
see "three" + nl
Class Display
Func printline
see copy("*",20) + nl
Class Count from Display
Func test
printline()
one()
two()
three()
printline()
42.28. mergemethods() Function 282

Class Count2 from Display
Func test
three()
two()
one()
printline()
Output:
********************
one
two
three
********************
three
two
one
********************
42.29 packagename() Function
We can know the package name of the latest sucessful import command using the packagename() function
Syntax:
packagename() --> Returns the package name of the latest sucessful import
Example:
load "weblib.ring"
import System.web
see packagename() # system.web
42.29. packagename() Function 283

CHAPTER
FORTYTHREE
STDLIB FUNCTIONS
In this chapter we are going to learn about functions in the stdlib.ring
Before using the functions in the library, We must load the library ﬁrst
load "stdlib.ring"
43.1 puts() function
print the value then print new line (nl)
Syntax:
puts(expr)
Example:
Load "stdlib.ring"
Puts("Hello, World!")
43.2 print() function
print string - support n,t and r
Also we can use #{variable_name} to insert variables values.
Syntax:
print(string) ---> String
Example:
print("nHello, WorldnnHow are you? tt I'm fine!n")
x=10 y=20
print("nx value = #{x} , y value = #{y} n")
43.3 Print2Str() Function
Syntax:
284

print2Str(string) ---> String
Example:
world = "World!"
mystring = print2str("Hello, #{world} nIn Year n#{2000+17} n")
see mystring + nl
Output:
Hello, World!
In Year
2017
43.4 getstring() function
Get input from the keyboard - return value as string
getstring() ---> string
43.5 getnumber() function
Get input from the keyboard - return value as number
getnumber() ---> number
43.6 apppath() function
Get the path of the application folder
Syntax:
AppPath() ---> The path as String
Example:
Load "stdlib.ring"
# Application Path
Puts("Test AppPath()")
See AppPath() + nl
43.7 justfilepath() function
Get the path of the file, remove the file name.
Syntax:
JustFilePath(cFile) ---> The path as String
43.4. getstring() function 285

Example:
load "stdlib.ring"
see justfilePath("b:ringapplicationsrnoternote.ring")
Output:
b:ringapplicationsrnote
43.8 justfilename() function
Get the file, remove the file path.
Syntax:
JustFileName(cFile) ---> The file name as String
Example:
load "stdlib.ring"
see justfileName("b:ringapplicationsrnoternote.ring")
Output:
rnote.ring
43.9 value() function
create a copy from a list or object
Syntax:
value(List) ---> new list
Example:
Load "stdlib.ring"
aList = 1:10
del(value(aList),1) # delete first item
see aList # print numbers from 1 to 10
43.10 times() function
Execute a Function nCount times
Syntax:
Times(nCount,function)
Example:
43.8. justfilename() function 286

Load "stdlib.ring"
Puts("Test Times()")
Times ( 3 , func { see "Hello, World!" + nl } )
43.11 map() function
Execute a Function on each list item
Syntax:
Map(alist,function) ---> List
Example:
Load "stdlib.ring"
Puts("Test Map()")
See Map( 1:10, func x { return x*x } )
43.12 ﬁlter() function
Execute a Function on each list item to ﬁlter items
Syntax:
Filter(alist,function) ---> List
Example:
Load "stdlib.ring"
Puts("Test Filter()")
See Filter( 1:10 , func x { if x <= 5 return true else return false ok } )
43.13 split() function
Convert string words to list items
Syntax:
Split(cstring,delimiter) ---> List
Example:
Load "stdlib.ring"
Puts("Test Split()")
See Split("one two three four five"," ")
43.11. map() function 287

43.14 splitmany() function
Convert string words to list items. Allow many delimiters.
Syntax:
SplitMany(cstring,delimiters as string or list) --> List
Example:
Load "stdlib.ring"
Puts("Test SplitMany()")
See SplitMany("one,two,three,four and five"," ,")
43.15 newlist() function
Create a two dimensional list
Syntax:
NewList(nRows,nColumns) ---> new list
Example:
Load "stdlib.ring"
Puts("Test Newlist()")
a1 = 3
a2 = 5
chrArray = newlist(a1,a2)
numArray = newlist(a1,a2)
chrArray[1][1] = "Hello"
numArray[1][1] = 987.2
See chrArray[1][1] + nl
See numArray[1][1] + nl
43.16 capitalized() function
Return a copy of a string with the ﬁrst letter capitalized
Syntax:
Capitalized(string) ---> string
Example:
Load "stdlib.ring"
Puts("Test Capitalized()")
See capitalized("welcome to the Ring Programming Language")
43.14. splitmany() function 288

43.17 isspecial() function
Check whether a character is special or not
Syntax:
IsSpecial(char) ---> True/False
Example:
Load "stdlib.ring"
Puts("Test Isspecial()")
See "Isspecial = " + isSpecial("%") + nl
43.18 isvowel() function
Check whether a character is vowel or not
Syntax:
IsVowel(char) ---> True/False
Example:
Load "stdlib.ring"
Puts("Test Isvowel()")
See "Isvowel = " + isVowel("c") + nl
43.19 linecount() function
Return the lines count in a text ﬁle.
Syntax:
LineCount(cFileName) ---> Lines Count as number
Example:
Load "stdlib.ring"
Puts("Test Linecount()")
See "the number of lines = " + lineCount("test.ring")
43.20 factorial() function
Return the factorial of a number
Syntax:
Factorial(number) ---> number
Example:
43.17. isspecial() function 289

Load "stdlib.ring"
Puts("Test Factorial()")
see "6 factorial is : " + Factorial(6)
43.21 fibonacci() function
Return the fibonacci number
Syntax:
Fibonacci(number) ---> number
Example:
Load "stdlib.ring"
Puts("Test Fibonacci()")
see "6 Fibonacci is : " + Fibonacci(6)
43.22 isprime() function
Check whether a number is prime or not
Syntax:
isprime(number) ---> Number
Example:
Load "stdlib.ring"
Puts("Test Isprime()")
if isPrime(16) see "16 is a prime number"
else see "16 is not a prime number" ok
43.23 sign() function
Returns an integer value indicating the sign of a number.
Syntax:
Sign(number) ---> number ( -1 = negative , 0 , 1 (positive) )
Example:
Load "stdlib.ring"
Puts("Test Sign()")
see "sign of 12 is = " + sign(12) + nl
43.21. fibonacci() function 290

43.24 list2file() function
Write list items to text file (each item in new line).
Syntax:
List2File(aList,cFileName)
Example:
Load "stdlib.ring"
# Test List2File
Puts("Test List2File()")
list2file(1:100,"myfile.txt")
43.25 file2list() function
Read text file and convert lines to list items
Syntax:
File2List(cFileName) ---> List
Example:
Load "stdlib.ring"
# Test File2List
Puts("Test File2List()")
see len(file2list("myfile.txt"))
43.26 startswith() function
Returns true if the given string starts with the specified substring.
Leading white spaces are ignored.
Syntax:
StartsWith(string, substring) ---> True/False
Example:
Load "stdlib.ring"
Puts("Test Startswith()")
see Startswith("CalmoSoft", "Calmo") + nl
43.27 endswith() function
Returns true if the given string ends with the specified substring.
Trailing white spaces are ignored.
43.24. list2file() function 291

Syntax:
Endswith(string, substring) ---> True/False
Example:
Load "stdlib.ring"
Puts("Test Endswith()")
see endsWith("CalmoSoft", "Soft") + nl
43.28 gcd() function
Finding of the greatest common divisor of two integers.
Syntax:
Gcd(number,number) ---> number
Example:
Load "stdlib.ring"
Puts("Test Gcd()")
see gcd (24, 32) + nl
43.29 lcm() function
Compute the least common multiple of two integers.
Syntax:
lcm(number,number) ---> number
Example:
Load "stdlib.ring"
Puts("Test Lcm()")
see Lcm(24,36) + nl
43.30 sumlist() function
Compute the sum of a list of integers.
Syntax:
sumlist(list) ---> number
Example:
Load "stdlib.ring"
Puts("Test Sumlist()")
43.28. gcd() function 292

aList = [1,2,3,4,5]
see Sumlist(aList) + nl
43.31 prodlist() function
Compute the product of a list of integers.
Syntax:
prodlist(list) ---> number
Example:
Load "stdlib.ring"
Puts("Test Prodlist()")
aList = [1,2,3,4,5]
see Prodlist(aList) + nl
43.32 evenorodd() function
Test whether an integer is even or odd.
Result of test (1=odd 2=even).
Syntax:
evenorodd(number) ---> 1 (odd) or 2 (even)
Example:
Load "stdlib.ring"
Puts("Test Evenorodd()")
nr = 17
see Evenorodd(nr) + nl
43.33 factors() function
Compute the factors of a positive integer.
Syntax:
factors(list) ---> list
Example:
Load "stdlib.ring"
Puts("Test Factors()")
n = 45
aList = factors(n)
see "Factors of " + n + " = "
for i = 1 to len(aList)
43.31. prodlist() function 293

see "" + aList[i] + " "
next
43.34 palindrome() function
Check if a sequence of characters is a palindrome or not.
Syntax:
Palindrome(String) ---> True/False
Example:
Load "stdlib.ring"
Puts("Test Palindrome()")
cString = "radar"
see Palindrome(cString)
43.35 isleapyear() function
Check whether a given year is a leap year in the Gregorian calendar.
Syntax:
Isleapyear(number) ---> True/False
Example:
Load "stdlib.ring"
Puts("Test Isleapyear()")
year = 2016
if Isleapyear(year) see "" + year + " is a leap year."
else see "" + year + " is not a leap year." ok
43.36 binarydigits() function
Compute the sequence of binary digits for a given non-negative integer.
Syntax:
binarydigits(number) ---> string
Example:
Load "stdlib.ring"
Puts("Test Binarydigits()")
b = 35
see "Binary digits of " + b + " = " + Binarydigits(b)
43.34. palindrome() function 294

43.37 matrixmulti() function
Multiply two matrices together.
Syntax:
Matrixmulti(List,List) ---> List
Example:
Load "stdlib.ring"
# Multiply two matrices together.
Puts("Test Matrixmulti()")
A = [[1,2,3], [4,5,6], [7,8,9]]
B = [[1,0,0], [0,1,0], [0,0,1]]
see Matrixmulti(A, B)
43.38 matrixtrans() function
Transpose an arbitrarily sized rectangular Matrix.
Syntax:
Matrixtrans(List) ---> List
Example:
Load "stdlib.ring"
# Transpose an arbitrarily sized rectangular Matrix.
Puts("Test Matrixtrans()")
matrix = [[78,19,30,12,36], [49,10,65,42,50], [30,93,24,78,10], [39,68,27,64,29]]
see Matrixtrans(matrix)
43.39 dayofweek() function
Return the day of the week of given date. (yyyy-mm-dd)
Syntax:
dayofweek(string) ---> string
Example:
Load "stdlib.ring"
# Return the day of the week of given date.
Puts("Test Dayofweek()")
date = "2016-04-24"
see "Data : " + date + " - Day : " + Dayofweek(date) + nl
43.37. matrixmulti() function 295

43.40 permutation() function
Generates all permutations of n different numerals.
Syntax:
permutation(list)
Example:
Load "stdlib.ring"
# Generates all permutations of n different numerals
Puts("Test Permutation()")
list = [1, 2, 3, 4]
for perm = 1 to 24
for i = 1 to len(list)
see list[i] + " "
next
see nl
Permutation(list)
next
43.41 readline() function
Read line from ﬁle
Syntax:
readline(fp) ---> string
Example:
Load "stdlib.ring"
# Read a file line by line.
Puts("Test Readline()")
fp = fopen("test.ring","r")
while not feof(fp)
See Readline(fp) end
fclose(fp)
43.42 substring() function
Return a position of a substring starting from a given position in a string.
Syntax:
Substring(str,substr,npos) ---> string
Example:
Load "stdlib.ring"
# Return a position of a substring starting from a given position in a string.
43.40. permutation() function 296

Puts("Test Substring()")
a = "abcxyzqweabc"
b = "abc"
i = 4
see substring(a,b,i)
43.43 changestring() function
Change substring from given position to a given position with another substring.
Syntax:
Changestring(cString, nPos1, nPos2, cSubstr) ---> cString
Example:
Load "stdlib.ring"
# Change substring from given position for given position with a substring.
Puts("Test Changestring()")
see Changestring("Rmasdg",2,5,"in") # Ring
43.44 sleep() function
Sleep for the given amount of time.
Syntax:
sleep(nSeconds)
Example:
Load "stdlib.ring"
Puts("Test Sleep()")
see "Wait 3 Seconds!"
Sleep(3)
see nl
43.45 ismainsourcefile() function
Check if the current file is the main source file
Syntax:
IsMainSourceFile() ---> True/False
Example:
Load "stdlib.ring"
if ismainsourcefile()
# code
ok
43.43. changestring() function 297

43.46 direxists() function
Check if directory exists
Syntax:
DirExists(String) ---> True/False
Example:
Load "stdlib.ring"
see "Check dir : b:ring "
puts( DirExists("b:ring") )
see "Check dir : C:ring "
Puts( DirExists("C:ring") )
43.47 makedir() function
Make Directory
Syntax:
MakeDir(String)
Example:
Load "stdlib.ring"
# Create Directory
puts("create Directory : myfolder")
makedir("myfolder")
43.48 fsize() function
The function return the ﬁle size in bytes.
Syntax:
FSize(File Handle) ---> Number (File Size in Bytes)
43.49 trimall() function
Remove all spaces and tabs characters from a string
Syntax:
TrimAll(cString) ---> cString # Without Spaces and Tabs
43.46. direxists() function 298

43.50 trimleft() function
Remove all spaces and tabs characters from the left side of a string
Syntax:
TrimLeft(cString) ---> cString # Without Spaces and Tabs from the left side
43.51 trimright() function
Remove all spaces and tabs characters from the right side of a string
Syntax:
TrimRight(cString) ---> cString # Without Spaces and Tabs from the right side
43.52 epochtime() function
Return the Epoch Time
Syntax:
EpochTime(cDate,cTime) ---> nEpochTime
Example:
see EpochTime( Date(), Time() )
43.53 SystemCmd() Function
We can execute system commands using the SystemCmd() function that outputs to a variable
Syntax:
SystemCmd(cCommand)
Example:
cYou = SystemCmd("whoami") # User Name logged in is output a variable
cThem = SystemCmd("dir c:Users") # Directory List is output to a variable
43.54 ListAllFiles() Function
Using this function we can quickly do a process on a group of ﬁles in a folder and it’s sub folders.
Syntax:
ListAllFiles(cFolder,cExtension) ---> List of Files
Example:
43.50. trimleft() function 299

aList = ListAllFiles("c:/ring/ringlibs","ring") # *.ring only
aList = sort(aList)
see aList
Example:
see listallfiles("b:/ring/ringlibs/weblib","") # All Files
43.54. ListAllFiles() Function 300

CHAPTER
FORTYFOUR
STDLIB CLASSES
In this chapter we are going to learn about the classes in the stdlib.ring
• StdBase Class
• String Class
• List Class
• Stack Class
• Queue Class
• HashTable Class
• Tree Class
• Math Class
• DateTime Class
• File Class
• System Class
• Debug Class
• DataType Class
• Conversion Class
• ODBC CLass
• MySQL Class
• SQLite Class
• Security Class
• Internet Class
44.1 StdBase Class
Attributes:
• vValue : Object Value
Methods:
301

Method Description/Output
Init(x) Set vValue Attribute to x value
Print() Print vValue
PrintLn() Print vValue then New Line
Size() return number represent the size of vValue
Value() return vValue
Set(x) Call Init(x)
44.2 String Class
Parent Class : StdBase Class
Methods:
Init(String|Number|List)
Lower() New String - Lower case characters
Upper() New String - Upper case characters
Left(x) New String - contains x characters from the left
Right(x) New String - contains x characters from the right
Lines() Number - Lines count
Trim() New String - Remove Spaces
Copy(x) New String - repeat string x times
strcmp(cString) Compare string with cString
tolist() List (String Lines to String Items)
toﬁle(cFileName) Write string to ﬁle
mid(nPos1,nPos2) New String - from nPos1 to nPos2
getfrom(nPos1) New String - from nPos1 to the end of the string
replace(cStr1,cStr2,lCase) New String - Replace cStr1 with cStr2 , lCase (True=Match Case)
split() List - Each Word as list item
startswith(substring) Return true if the start starts with a substring
endswith(substring) Return true if the start ends with a substring
Example:
Load "stdlib.ring"
See "Testing the String Class" + nl
oString = new string("Hello, World!")
oString.println()
oString.upper().println()
oString.lower().println()
oString.left(5).println()
oString.right(6).println()
oString = new string("Hi" + nl + "Hello" )
See oString.lines() + nl
oString = new string(" Welcome ")
oString.println()
oString.trim().println()
oString = new string("Hello! ")
oString.copy(3).println()
see oString.strcmp("Hello! ") + nl
see oString.strcmp("Hello ") + nl
see oString.strcmp("Hello!! ") + nl
oString = new string(["one","two","three"])
44.2. String Class 302

oString.print()
see oString.lines() + nl
oString = new String(1234)
oString.println()
oString = new String("one"+nl+"two"+nl+"three")
aList = oString.tolist()
see "List Items" + nl See aList
oString = new String( "Welcome to the Ring programming language")
See "the - position : " + oString.pos("the") + nl
oString = oString.getfrom(oString.pos("Ring"))
oString.println()
oString.mid(1,4).println()
oString = oString.replace("Ring","***Ring***",true)
oString.println()
oString = oString.replace("ring","***Ring***",false)
oString.println()
oString1 = new string("First")
oString2 = new string("Second")
oString = oString1 + oString2
oString.println()
oString = oString1 * 3
oString.println()
for t in ostring see t next
oString.tofile("test.txt")
oString = new string("one two three")
see nl
see ostring.split()
oString {
set("Hello") println()
set("How are you?") println()
}
Output:
Testing the String Class
Hello, World!
HELLO, WORLD!
hello, world!
Hello
World!
2
Welcome
Welcome
Hello! Hello! Hello!
0
1
-1
one
two
three
4
1234
List Items
one
two
three
the - position : 12
Ring programming language
44.2. String Class 303

Ring
***Ring*** programming language
******Ring****** programming language
FirstSecond
FirstFirstFirst
FirstFirstFirst
one
two
three
Hello
How are you?
44.3 List Class
Parent Class : StdBase Class
Methods:
Init(String|List)
Add(Value) Add item to the list
Delete(nIndex) Delete item from the list
Item(nIndex) Get item from the list
First() Get the ﬁrst item in the list
Last() Get the last item in the list
Set(nIndex,Value) Set item value
FindInColumn(nCol,Value) Find item in a column
Sort() Sort items - return new list
Reverse() Reverse items - return new list
Insert(nIndex,Value) Inset Item after nIndex
example:
Load "stdlib.ring"
oList = new list ( [1,2,3] )
oList.Add(4)
oList.print()
see oList.item(1) + nl
oList.delete(4)
oList.print()
see oList.first() + nl
see oList.last() + nl
oList { set(1,"one") set(2,"two") set(3,"three") print() }
see oList.find("two") + nl
oList.sort().print()
oList.reverse().print()
oList.insert(2,"nice")
oList.print()
oList = new list ( [ [1,"one"],[2,"two"],[3,"three"] ] )
oList.print()
see "Search two : " + oList.findincolumn(2,"two") + nl
see "Search 1 : " + oList.findincolumn(1,1) + nl
oList = new list ( [ "Egypt" , "USA" , "KSA" ] )
for x in oList
44.3. List Class 304

see x + nl
next
oList = new list ( [1,2,3,4] )
oList + [5,6,7]
oList.print()
oList = new list ( ["one","two"] )
oList2 = new list ( ["three","four"] )
oList + oList2
oList.print()
output:
1
2
3
4
1
1
2
3
1
3
one
two
three
2
one
three
two
three
two
one
one
two
nice
three
**********
1
one
2
two
3
three
Search two : 2
Search 1 : 1
Egypt
USA
KSA
1
2
3
4
5
6
7
one
two
three
44.3. List Class 305

four
44.4 Stack Class
Parent Class : List Class
Methods:
Push(Value) Push item to the stack
Pop() Pop item from the stack
Print() Print the stack items
example:
Load "stdlib.ring"
oStack = new Stack
oStack.push(1)
oStack.push(2)
oStack.push(3)
see oStack.pop() + nl
oStack.push(4)
oStack { push("one") push("two") push("three") }
oStack.print()
output:
3
2
1
4
three
two
one
44.5 Queue Class
Methods:
Remove() Remove item from the Queue.
example:
Load "stdlib.ring"
oQueue = new Queue
oQueue.add(1)
44.4. Stack Class 306

oQueue.add(2)
oQueue.add(3)
see oQueue.remove() + nl
oQueue.add(4)
oQueue { add("one") add("two") add("three") }
oQueue.print()
output:
1
2
3
4
one
two
three
44.6 HashTable Class
Methods:
Init(List)
Add(cKey,Value) Add item to the HashTable
Set(cKey,Value) Set item value using the Key
GetValue(cKey) Get item value using the Key
Contains(cKey) Check if the HashTable contains item using the Key
Index(cKey) Get the item index using the Key
example:
Load "stdlib.ring"
ohashtable = new hashtable
See "Test the hashtable Class Methods" + nl
ohashtable {
Add("Egypt","Cairo")
Add("KSA","Riyadh")
see self["Egypt"] + nl
see self["KSA"] + nl
see contains("Egypt") + nl
see contains("USA") + nl
see index("KSA") + NL
print()
delete(index("KSA"))
print()
}
output:
44.6. HashTable Class 307

Test the hashtable Class Methods
Cairo
Riyadh
1
0
2
Egypt
Cairo
KSA
Riyadh
************************************************************
Egypt
Cairo
44.7 Tree Class
Data:
Attribute Description
Data Node Value
Children Children List
Methods:
set(value) Set the node value.
value() Get the node value.
Add(value) Add new child.
parent() Get the parent node.
print() Print the tree nodes.
example:
Load "stdlib.ring"
otree = new tree
See "Test the tree Class Methods" + nl
otree {
set("The first step") # set the root node value
see value() + nl
Add("one")
Add("two")
Add("three") {
Add("3.1")
Add("3.2")
Add("3.3")
see children
}
see children
oTree.children[2] {
Add("2.1") Add("2.2") Add("2.3") {
Add("2.3.1") Add("2.3.2") Add("test")
}
}
oTree.children[2].children[3].children[3].set("2.3.3")
}
44.7. Tree Class 308

oTree.print()
output:
Test the tree Class Methods
The first step
data: 3.1
parent: List...
children: List...
data: 3.2
parent: List...
children: List...
data: 3.3
parent: List...
children: List...
data: one
parent: List...
children: List...
data: two
parent: List...
children: List...
data: three
parent: List...
children: List...
************************************************************
one
two
2.1
2.2
2.3
2.3.1
2.3.2
2.3.3
three
3.1
3.2
3.3
44.8 Math Class
Methods:
44.8. Math Class 309

Method Description
sin(x) Returns the sine of an angle of x radians
cos(x) Returns the cosine of an angle of x radians
tan(x) Returns the tangent of an angle of x radians
asin(x) Returns the principal value of the arc sine of x, expressed in radians
acos(x) Returns the principal value of the arc cosine of x, expressed in radians
atan(x) Returns the principal value of the arc tangent of x, expressed in radians
atan2(y,x) Returns the principal arc tangent of y/x, in the interval [-pi,+pi] radians
sinh(x) Returns the hyperbolic sine of x radians
cosh(x) Returns the hyperbolic cosine of x radians
tanh(x) Returns the hyperbolic tangent of x radians
exp(x) Returns the value of e raised to the xth power
log(x) Returns the natural logarithm of x
log10(x) Returns the common logarithm (base-10 logarithm) of x
ceil(x) Returns the smallest integer value greater than or equal to x
ﬂoor(x) Returns the largest integer value less than or equal to x
fabs(x) Returns the absolute value of x.
pow(x,y) Returns x raised to the power of y
sqrt(x) Returns the square root of x
random(x) Returns a random number in the range [0,x]
unsigned(n,n,c) Perform operation using unsigned numbers
decimals(n) Determine the decimals digits after the point in ﬂoat/double numbers
example:
Load "stdlib.ring"
oMath = new Math
See "Test the Math Class Methods" + nl
See "Sin(0) = " + oMath.sin(0) + nl
See "Sin(90) radians = " + oMath.sin(90) + nl
See "Sin(90) degree = " + oMath.sin(90*3.14/180) + nl
See "Cos(0) = " + oMath.cos(0) + nl
See "Cos(90) radians = " + oMath.cos(90) + nl
See "Cos(90) degree = " +oMath. cos(90*3.14/180) + nl
See "Tan(0) = " + oMath.tan(0) + nl
See "Tan(90) radians = " + oMath.tan(90) + nl
See "Tan(90) degree = " + oMath.tan(90*3.14/180) + nl
See "asin(0) = " + oMath.asin(0) + nl
See "acos(0) = " + oMath.acos(0) + nl
See "atan(0) = " + oMath.atan(0) + nl
See "atan2(1,1) = " +oMath. atan2(1,1) + nl
See "sinh(0) = " + oMath.sinh(0) + nl
See "sinh(1) = " + oMath.sinh(1) + nl
See "cosh(0) = " + oMath.cosh(0) + nl
See "cosh(1) = " + oMath.cosh(1) + nl
See "tanh(0) = " + oMath.tanh(0) + nl
See "tanh(1) = " + oMath.tanh(1) + nl
See "exp(0) = " + oMath.exp(0) + nl
See "exp(1) = " + oMath.exp(1) + nl
See "log(1) = " + oMath.log(1) + nl

See "log(2) = " + oMath.log(2) + nl
See "log10(1) = " + oMath.log10(1) + nl
See "Ceil(1.12) = " + oMath.Ceil(1.12) + nl
See "Ceil(1.72) = " + oMath.Ceil(1.72) + nl
See "Floor(1.12) = " + oMath.floor(1.12) + nl
See "Floor(1.72) = " + oMath.floor(1.72) + nl
See "fabs(1.12) = " + oMath.fabs(1.12) + nl
See "fabs(1.72) = " + oMath.fabs(1.72) + nl
See "pow(2,3) = " + oMath.pow(2,3) + nl
see "sqrt(16) = " + oMath.sqrt(16) + nl
for x = 1 to 20
see "Random number Max (100) : " + oMath.random(100) + nl
next
x = 1.1234567890123
for d = 0 to 14
oMath.decimals(d)
see x + nl
next
cKey = "hello"
h = 0
for x in cKey
h = oMath.unsigned(h,ascii(x),"+")
h = oMath.unsigned(h,oMath.unsigned(h,10,"<<"),"+")
r = oMath.unsigned(h,6,">>")
h = oMath.unsigned(h, r,"^")
next
h = oMath.unsigned(h,oMath.unsigned(h,11,">>"),"^")
see "Hash : " + h
output:
Test the Math Class Methods
Sin(0) = 0
Sin(90) radians = 0.89
Sin(90) degree = 1.00
Cos(0) = 1
Cos(90) radians = -0.45
Cos(90) degree = 0.00
Tan(0) = 0
Tan(90) radians = -2.00
Tan(90) degree = 1255.77
asin(0) = 0
acos(0) = 1.57
atan(0) = 0
atan2(1,1) = 0.79

sinh(0) = 0
sinh(1) = 1.18
cosh(0) = 1
cosh(1) = 1.54
tanh(0) = 0
tanh(1) = 0.76
exp(0) = 1
exp(1) = 2.72
log(1) = 0
log(2) = 0.69
log10(1) = 0
log10(2) = 0.30
log10(10) = 1
Ceil(1.12) = 2
Ceil(1.72) = 2
Floor(1.12) = 1
Floor(1.72) = 1
fabs(1.12) = 1.12
fabs(1.72) = 1.72
pow(2,3) = 8
sqrt(16) = 4
Random number Max (100) : 87
1
1.1
1.12
1.123
1.1235
1.12346
1.123457
1.1234568
1.12345679
1.123456789
1.1234567890
1.12345678901
1.123456789012
1.1234567890123
1.12345678901230
Hash : 3372029979.00000000000000

44.9 DateTime Class
Methods:
clock() The number of clock ticks from program start.
time() Get the system time.
date() Get the date.
timelist() List contains the date and the time information.
adddays(cDate,nDays) Return Date from cDate and after nDays
diffdays(cDate1,cDate2) Return the Number of days (cDate1 - cDate2)
example:
Load "stdlib.ring"
oDateTime = new datetime
See "Test the datetime Class Methods" + nl
See "Calculate performance" + nl
t1 = oDateTime.clock()
for x = 1 to 1000000 next
see oDateTime.clock() - t1 + nl
See "Time : " + oDateTime.time() + nl
See "Date : " + oDateTime.date() + nl
See oDateTime.TimeList()
See "Month Name : " + oDateTime.TimeList()[4]
cDate = oDateTime.date()
see cDate + nl
cDate = oDateTime.adddays(cDate,10)
see cDate + nl
cDate1 = oDateTime.date()
see cDate1 + nl
cDate2 = oDateTime.adddays(cDate1,10)
see cDate2 + nl
see "DiffDays = " + oDateTime.diffdays(cDate1,cDate2) + nl
see "DiffDays = " + oDateTime.diffdays(cDate2,cDate1) + nl
output:
Test the datetime Class Methods
Calculate performance
85
Time : 02:53:35
Date : 31/08/2016
Wed
Wednesday
Aug
August
08/31/16 02:53:35
31
44.9. DateTime Class 313

02
02
244
08
53
AM
35
35
3
08/31/16
02:53:35
16
2016
Arab Standard Time
%
Month Name : August31/08/2016
10/09/2016
31/08/2016
10/09/2016
DiffDays = -10
DiffDays = 10
44.10 File Class
Methods:
44.10. File Class 314

read(cFileName) Read the file content
write(cFileName,cStr) Write string to file
dir(cFolderPath) Get the folder contents (files & sub folders)
rename(cOld,cNew) Rename files using the Rename() function
remove(cFileName) Delete a file using the Remove() function
open(cFileName,cMode) Open a file using the Fopen() function
close() Close file
flush() Flushes the output buffer of a stream
reopen(cFileName,cMode) Open another file using the same file handle
tempfile() Creates a temp. file (binary).
seek(noffset,nwhence) Set the file position of the stream
tell() Know the current file position of a stream
rewind() Set the file position to the beginning of the file
getpos() Get handle to the current file position
setpos(poshandle) Set the current file position
clearerr() Clear the EOF error and the error indicators of a stream
eof() Test the end-of-file indicator
error() Test the error indicator
perror(cErrorMessage) Print error message to the stderr
getc() Get the next character from the stream
gets(nsize) Read new line from the stream
putc(cchar) Write a character to the stream
puts(cStr) Write a string to the stream
ungetc(cchar) Push a character to the stream
fread(nsize) Read data from a stream
fwrite(cString) Write data to a stream
exists(cFileName) Check if a file exists
example:
Load "stdlib.ring"
ofile = new file
See "Test the file Class Methods" + nl
see ofile.read(filename())
see nl
ofile.open(filename(),"r")
see ofile.gets(100) + nl
ofile.close()
44.11 System Class
Methods:
44.11. System Class 315

system() Execute system commands
sysget() Get environment variables
ismsdos() Check if the operating system is MSDOS or not
iswindows() Check if the operating system is Windows or not
iswindows64() Check if the operating system is Windows 64bit or not
isunix() Check if the operating system is Unix or not
ismacosx() Check if the operating system is Mac OS X or not
islinux() Check if the operating system is Linux or not
isfreebsd() Check if the operating system is FreeBSD or not
isandroid() Check if the operating system is Android or not
windowsnl() Get the windows new line string
sysargv() Get the command line arguments passed to the ring script
ﬁlename() Get the active source ﬁle
example:
Load "stdlib.ring"
oSystem = new System
See "Test the System Class Methods" + nl
oSystem.system("dir")
see oSystem.sysget("path") + nl
see oSystem.ismsdos() + nl
see oSystem.iswindows() + nl
see oSystem.iswindows64() + nl
see oSystem.isunix() + nl
see oSystem.ismacosx() + nl
see oSystem.islinux() + nl
see oSystem.isfreebsd() + nl
see oSystem.isandroid() + nl
see oSystem.windowsnl() + nl
see oSystem.sysargv() + nl
see oSystem.filename() + nl
44.12 Debug Class
Methods:
eval(cCode) Execute code during the runtime from string.
raise(cError) Raise an exception.
assert(cCondition) Test condition before executing the code.
example:
Load "stdlib.ring"
oDebug = new Debug
See "Test the Debug Class Methods" + nl
oDebug.eval("see 'Hello'+nl")
try
x = 10
oDebug.assert(x=11)
44.12. Debug Class 316

catch see "assert" + nl done
raise("Error!")
44.13 DataType Class
Methods:
isstring(vValue) We can know if the value is a string or not.
isnumber(vValue) We can know if the value is a number or not.
islist(vValue) We can know if the value is a list or not.
type(vValue) Know the type of a value
isnull(vValue) Check the value to know if it’s null or not.
isalnum(vValue) 1 if the value is digit/letter or 0 if not
isalpha(vValue) 1 if the value is a letter or 0 if not
iscntrl(vValue) 1 if the value is a control character (no printing position)
isdigit(vValue) 1 if the value is a digit or 0 if not
isgraph(vValue) 1 if the value can be printed (Except space) or 0 if not
islower(vValue) 1 if the value is lowercase letter or 0 if not
isprint(vValue) 1 if the value occupies a printing position or 0 if not
ispunct(vValue) 1 if the value is a punctuation character or 0 if not
isspace(vValue) 1 if the value is a white-space or 0 if not
isupper(vValue) 1 if the value is an uppercase alphabetic letter or 0 if not
isxdigit(vValue) 1 if the value is a hexdecimal digit character or 0 if not
example:
Load "stdlib.ring"
oDataType = new DataType
See "Test the DataType Class Methods" + nl
see oDataType.isstring("test") + nl
see oDataType.isnumber(1) + nl
see oDataType.islist(1:3) + nl
see oDataType.type("test") + nl
see oDataType.isnull(null) + nl
see oDataType.isalnum("Hello") + nl + # print 1
oDataType.isalnum("123456") + nl + # print 1
oDataType.isalnum("ABCabc123") + nl + # print 1
oDataType.isalnum("How are you") + nl # print 0 because of spaces
see oDataType.isalpha("Hello") + nl + # print 1
oDataType.isalpha("123456") + nl + # print 0
oDataType.isalpha("ABCabc123") + nl + # print 0
oDataType.isalpha("How are you") + nl # print 0
See oDataType.iscntrl("hello") + nl + # print 0
oDataType.iscntrl(nl) # print 1
see oDataType.isdigit("0123456789") + nl + # print 1
oDataType.isdigit("0123a") + nl
see oDataType.isgraph("abcdef") + nl + # print 1
oDataType.isgraph("abc def") + nl # print 0
see oDataType.islower("abcDEF") + nl + # print 0
oDataType.islower("ghi") + nl # print 1
see oDataType.isprint("Hello") + nl + # print 1
oDataType.isprint("Nice to see you") + nl + # print 1
oDataType.isprint(nl) + nl # print 0
44.13. DataType Class 317

see oDataType.isprint("Hello") + nl # print 1
see oDataType.isupper("welcome") + nl + # print 0
oDataType.isupper("WELCOME") + nl # print 1
see oDataType.isxdigit("0123456789abcdef") + nl + # print 1
oDataType.isxdigit("123z") # print 0
Output:
Test the DataType Class Methods
1
1
1
STRING
1
1
1
1
0
1
0
0
0
0
11
0
1
0
0
1
1
1
0
1
0
1
1
0
44.14 Conversion Class
Methods:
number(vValue) Convert strings to numbers.
string(vValue) Convert numbers to strings.
ascii(vValue) Get the ASCII code for a letter.
char(vValue) Convert the ASCII code to character.
hex(vValue) Convert decimal to hexadecimal.
dec(vValue) Convert hexadecimal to decimal.
str2hex(vValue) Convert string characters to hexadecimal characters.
hex2str(vValue) Convert hexadecimal characters to string.
example:
Load "stdlib.ring"
44.14. Conversion Class 318

oConversion = new conversion
See "Test the conversion Class Methods" + nl
See oConversion.number("3") + 5 + nl
See oConversion.string(3) + "5" + nl
See oConversion.Ascii("m") + nl
See oConversion.char(77) + nl
see oConversion.hex(162) + nl
see oConversion.dec("a2") + nl
cHex = oConversion.str2hex("Hello")
see cHex + nl
see oConversion.hex2str(cHex) + nl
Output:
Test the conversion Class Methods
8
35
109
M
a2
162
48656c6c6f
Hello
44.15 ODBC Class
Methods:
drivers() Get a list of ODBC drivers.
datasources() Get a list of ODBC data sources.
close() Free resources.
connect(cConString) Connect to the database.
disconnect() Close the connection.
execute(cSQL) Execute SQL Statements
colcount() Get columns count in the query result
fetch() Fetch a row from the query result
getdata(nCol) Get column value from the fetched row
tables() Get a list of tables inside the database
columns(cTableName) Get a list of columns inside the table
autocommit(lStatus) Enable or disable the auto commit feature
commit() Commit updates to the database
rollback() Rollback updates to the database
example:
Load "stdlib.ring"
oodbc = new odbc
See "Test the odbc Class Methods" + nl
oODBC {
see drivers()
see datasources()
See "Connect to database" + nl
see connect("DBQ=test.mdb;Driver={Microsoft Access Driver (*.mdb)}") + nl
See "Select data" + nl
44.15. ODBC Class 319

see execute("select * from person") + nl
nMax = colcount()
See "Columns Count : " + nMax + nl
while fetch()
See "Row data:" + nl
for x = 1 to nMax
see getdata(x) + " - "
next
end
See "Close database..." + nl
disconnect()
close()
}
44.16 MySQL Class
Methods:
info() Return string contains the MySQL Client version.
error() Get the error message from the MySQL Client.
connect(cServer,cUser,cPass,cDatabase) Connect to the MySQL database server.
close() Close the connection to the MySQL database.
query(cQuery) Execute SQL queries.
insert_id() Get the inserted row id.
result() Get the query result (data without column names).
next_result() Move to the next query result.
columns() Get a list of columns names.
result2() Get all of the column names then the query result in one list.
escape_string(cStr) Before storing binary data and special characters in the database.
autocommit(lStatus) Enable or disable the auto commit feature.
commit() Commit updates to the database.
rollback() Rollback updates to the database.
example:
Load "stdlib.ring"
omysql = new mysql
See "Test the MySQL Class Methods" + nl
omysql {
see info() + nl
connect("localhost", "root", "root","mahdb")
see "Execute Query" + nl
query("SELECT * FROM Employee")
see "Print Result" + nl
see result2()
see "Close database" + nl
close()
}
Output:
Test the MySQL Class Methods
5.5.30
44.16. MySQL Class 320

Execute Query
Print Result
Id
Name
Salary
1
Mahmoud
15000
2
Samir
16000
3
Fayed
17000
Close database
44.17 SQLite Class
Methods:
open(cDatabase) Open Database.
close() Close Database.
errormessage() Get Error Message.
execute(cSQL) Execute Query.
example:
Load "stdlib.ring"
osqlite = new sqlite
See "Test the sqlite Class Methods" + nl
osqlite {
open("test.db")
sql = "CREATE TABLE COMPANY(" +
"ID INT PRIMARY KEY NOT NULL," +
"NAME TEXT NOT NULL," +
"AGE INT NOT NULL," +
"ADDRESS CHAR(50)," +
"SALARY REAL );"
execute(sql)
sql = "INSERT INTO COMPANY (ID,NAME,AGE,ADDRESS,SALARY) " +
"VALUES (1, 'Mahmoud', 29, 'Jeddah', 20000.00 ); " +
"INSERT INTO COMPANY (ID,NAME,AGE,ADDRESS,SALARY) " +
"VALUES (2, 'Ahmed', 27, 'Jeddah', 15000.00 ); " +
"INSERT INTO COMPANY (ID,NAME,AGE,ADDRESS,SALARY)" +
"VALUES (3, 'Mohammed', 31, 'Egypt', 20000.00 );" +
"INSERT INTO COMPANY (ID,NAME,AGE,ADDRESS,SALARY)" +
"VALUES (4, 'Ibrahim', 24, 'Egypt ', 65000.00 );"
execute(sql)
aResult = execute("select * from COMPANY")
for x in aResult
for t in x
44.17. SQLite Class 321

see t[2] + nl
next
next
for x in aResult
see x["name"] + nl
next
close()
}
Output:
Test the sqlite Class Methods
1
Mahmoud
29
Jeddah
20000.0
2
Ahmed
27
Jeddah
15000.0
3
Mohammed
31
Egypt
20000.0
4
Ibrahim
24
Egypt
65000.0
**************************************************
Mahmoud
Ahmed
Mohammed
Ibrahim
44.18 Security Class
Methods:
md5(cString) Calculate the MD5 hash.
sha1(cString) Calculate the SHA1 hash.
encrypt(cString,cKey,cIV) Cncrypts the data using the Blowﬁsh algorithm.
decrypt(cString,cKey,cIV) Decrypt the data encrypted using the Encrypt() method.
randbytes(nSize) Generate a string of pseudo-random bytes.
example:
44.18. Security Class 322

Load "stdlib.ring"
osecuirty = new secuirty
See "Test the secuirty Class Methods" + nl
oSecuirty {
see md5("hello") + nl +
sha1("hello") + nl + sha256("hello") + nl +
sha512("hello") + nl + sha384("hello") + nl +
sha256("hello") + nl
list = 0:15 cKey="" for x in list cKey += char(x) next
list = 1:8 cIV = "" for x in list cIV += char(x) next
cCipher = encrypt("hello",cKey,cIV)
see cCipher + nl + decrypt(cCipher,cKey,cIV) + nl
}
44.19 Internet Class
Methods:
• download(cURL)
• sendemail(cSMTPServer,cEmail,cPassword,cSender,cReceiver,cCC,cTitle,cContent)
example:
Load "stdlib.ring"
ointernet = new internet
See "Test the internet Class Methods" + nl
ointernet {
see download("www.ring-lang.sf.net")
}
44.19. Internet Class 323

CHAPTER
FORTYFIVE
DECLARATIVE PROGRAMMING USING NESTED STRUCTURES
In this chapter we are going to learn how to build declarative programming world using nested structures on the top of
object oriented.
We will learn about
• Creating Objects inside Lists
• Composition and Returning Objects and Lists by Reference
• Executing code after the end of object access
• Declarative Programming on the top of Object-Oriented
45.1 Creating Objects inside Lists
We can create objects inside lists during list deﬁnition. Also we can add objects to the list at any time using the Add()
function or the + operator.
Example:
alist = [new point, new point, new point] # create list contains three objects
alist + [1,2,3] # add another item to the list
see "Item 4 is a list contains 3 items" + nl
see alist[4]
add(alist , new point)
alist + new point
alist[5] { x = 100 y = 200 z = 300 }
alist[6] { x = 50 y = 150 z = 250 }
see "Object inside item 5" + nl
see alist[5]
see "Object inside item 6" + nl
see alist[6]
class point x y z
Output:
Item 4 is a list contains 3 items
1
2
324

3
Object inside item 5
x: 100.000000
y: 200.000000
z: 300.000000
Object inside item 6
x: 50.000000
y: 150.000000
z: 250.000000
45.2 Composition and Returning Objects and Lists by Reference
When we use composition and have object as one of the class attributes, when we return that object it will be returned
by reference.
if the called used the assignment operator, another copy of the object will be created.
The caller can avoid using the assignment operator and use the returned reference directly to access the object.
The same is done also if the attribute is a list (not object).
Note: Objects and Lists are treated using the same rules. When you pass them to function they are passed by
reference,
when you return them from functions they are returned by value except if it’s an object attribute where a return by
reference will be done.
Example:
o1 = new Container
myobj = o1.addobj() # the assignment will create another copy
myobj.x = 100
myobj.y = 200
myobj.z = 300
see o1.aobjs[1] # print the object inside the container
see myobj # print the copy
Class Container
aObjs = []
func addobj
aobjs + new point
return aobjs[len(aobjs)] # return object by reference
Class point
x = 10
y = 20
z = 30
Output:
x: 10.000000
y: 20.000000
z: 30.000000
x: 100.000000
y: 200.000000
z: 300.000000
45.2. Composition and Returning Objects and Lists by Reference 325

Example(2):
func main
o1 = new screen {
content[point()] {
x = 100
y = 200
z = 300
}
content[point()] {
x = 50
y = 150
z = 250
}
}
see o1.content[1]
see o1.content[2]
Class Screen
content = []
func point
content + new point
return len(content)
Class point
x = 10
y = 20
z = 30
Output:
x: 100.000000
y: 200.000000
z: 300.000000
x: 50.000000
y: 150.000000
z: 250.000000
Example(3):
func main
o1 = New Screen {
point() { # access the object using reference
x = 100
y = 200
z = 300
}
point() { # access the object using reference
x = 50
y = 150
z = 250
}
}
see o1.content[1]
see o1.content[2]
Class Screen
content = []
func point
content + new point
45.2. Composition and Returning Objects and Lists by Reference 326

return content[len(content)] # return the object by reference
Class point x=10 y=20 z=30
Output:
x: 100.000000
y: 200.000000
z: 300.000000
x: 50.000000
y: 150.000000
z: 250.000000
45.3 Executing code after the end of object access
We can access an object using { } to use object attributes and methods.
if the object contains a method called BraceEnd(), it will be executed before the end of the object access.
Example:
New Point { See "How are you?" + nl }
Class Point x y z
func braceend
see "I'm fine, Thank you!" + nl
Output:
How are you?
I'm fine, Thank you!
45.4 Declarative Programming on the top of Object-Oriented
The next features enable us to build and use declartive programming environment using nested structures on the top
of object oriented
• using {} to access the object attributes and methods
• BraceEnd() Method
• returning objects by reference
• Setter/Getter Methods (optional)
Example:
# Declartive Programming (Nested Structures)
Screen()
{
point()
{
x = 100
y = 200
z = 300
45.3. Executing code after the end of object access 327

}
point()
{
x = 50
y = 150
z = 250
}
}
# Functions and Classes
Func screen return new screen
Class Screen
content = []
func point
content + new point
return content[len(content)]
func braceend
see "I have " + len(content) + " points!"
Class point
x=10 y=20 z=30
func braceend
see self
Output:
x: 100.000000
y: 200.000000
z: 300.000000
x: 50.000000
y: 150.000000
z: 250.000000
I have 2 points!
45.5 More beautiful Code
We can get better results and a more beautiful code when we can avoid writing () after the method name when
the methods doesn’t take parameters. This feature is not provided directly by the Ring language because there is a
difference between object methods and object attributes. We can get a similar effect on the syntax of the code when
we define a getter method for the object attribute. For example instead of defining the point() method. we will define
the point attribute then the getpoint() method that will be executed once you try to get the value of the point attribute.
since we write the variable name direcly without () we can write point instead of point() and the method getpoint()
will create the object and return the object reference for us.
Example:
new Container
{
45.5. More beautiful Code 328

The Ring programming language version 1.5 book - Part 6 of 31

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