The Ring programming language version 1.9 book - Part 86 of 210
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The document introduces the Type Hints library in Ring, which allows adding type information to source code. This helps tools like code editors and static analysis. The library supports basic types like int and string, as well as user-defined types. Type hints are added to function prototypes using parentheses and by assigning variables. While Ring is dynamically typed, type hints do not add type checking but provide metadata for tools. Examples demonstrate defining typed functions and using type hints inside code and with user classes.
![Ring Documentation, Release 1.9
test() { main([:one,:two,:three]) }
myclass func test() {
see "Testing User Types!" + nl
return new myclass
}
package mypackage {
public class myclass {
public static void func main(list args) {
see "welcome" + nl
see args
}
}
}
72.4 Using Types inside Code
Also you can use the types inside the code (not only the function prototype)
Example:
load "typehints.ring"
int sum = sum(3,4)
string msg = sayHello("Mahmoud")
see "Sum = " + sum + nl + msg + nl
int func sum(int x,int y) {
return x+y ;
}
string func sayHello(string name) {
return "Hello " + name ;
}
72.5 Rules
âą To use the types in the function prototype you must use â(â and â)â around parameters
âą To use the types in the function code, You must set the variable value (Assignment).
The next types are deïŹned by the library
# Low Level Types
char
unsigned
signed
int
short
long
float
72.4. Using Types inside Code 827](https://image.slidesharecdn.com/851ring-181111125713/85/The-Ring-programming-language-version-1-9-book-Part-86-of-210-9-320.jpg)
The Ring programming language version 1.9 book - Part 86 of 210
- 1. Ring Documentation, Release 1.9 translation to other languages like Arabic, French and so on. Tip: The effect of LoadSyntax command is related to the current source code ïŹle only. 71.4 Using â()â around the function parameters We can use () around the function parameters (optional). Example: hello() sum(3,4) func hello() see "Hello" + nl func sum(x,y) see x+y+nl Output: Hello 7 Example: myfunc = func x,y { see x + y + nl } call myfunc (3,4) myfunc2 = func (x,y) { see x+y+nl } call myfunc(3,4) Output: 7 7 71.5 Using Semi-colon after and between statements In Ring we can use semi-colon after and between statements (optional). Example: # Using semi-colon is optional see "Hello" + nl ; see "How are you?" + nl ; see "Welcome to Ring" + nl ; one() ; two() ; three() ; func one ; see "one" + nl ; func two ; see "two" + nl ; func three ; see "three" + nl ; Output: 71.4. Using â()â around the function parameters 819
- 2. Ring Documentation, Release 1.9 Hello How are you? Welcome to Ring one two three 71.6 Using $ and @ in the start of the variable name You can use any unicode character in the variable name also we can use $ and @ in the name. This feature may help, for example we can start global variables with $ and the object attributes with @. In other languages like Ruby this is the rule, In the Ring language this is just an option without any force from the Compiler. example: $global_variable = 5 new test { hello() } class test @instance_variable = 10 func hello local_variable = 15 see "Global : " + $global_variable + nl + "Instance : " + @instance_variable + nl + "Local : " + local_variable + nl Output: Global : 5 Instance : 10 Local : 15 71.7 Using the âelseifâ keyword as âbutâ in if statement if you donât like the âbutâ keyword in if statement Then you can use the âelseifâ keyword. Example: give x if x = 1 see "one" elseif x=2 see "two" elseif x=3 see "three" elseif x=4 see "four" else see "other" ok see nl 71.6. Using $ and @ in the start of the variable name 820
- 3. Ring Documentation, Release 1.9 71.8 Using the âelseâ keyword as âotherâ in switch statement if you donât like the âotherâ keyword in switch statement Then you can use the âelseâ keyword. Also you can replace âelseâ with âotherâ in if statement. i.e. âotherâ keyword is the same as âelseâ keyword. Example: x = 1 switch x on 10 see "10" + nl else see "not 10" + nl end Output: not 10 71.9 Using the âendâ keyword in different control structures We can use the âendâ keyword to close different control structures âą If statement âą For loop âą Switch âą While âą Try-Catch Example: see "if statement.." + nl x = 1 if x = 1 see "one" + nl elseif x=2 see "two" + nl elseif x=3 see "three" + nl end see "for loop.." + nl for t = 1 to 10 see t end see nl see "switch..." + nl x = 1 switch x on 1 see "one" + nl on 2 see "two" + nl end 71.8. Using the âelseâ keyword as âotherâ in switch statement 821
- 4. Ring Documentation, Release 1.9 see "try catch..." + nl try x = 1 / 0 catch see "catching error" + nl end Output: if statement.. one for loop.. 12345678910 switch... one try catch... catching error 71.10 Using braces to start and end different control structures We can use braces { } to start and end different control structures âą If statement âą For loop âą Switch âą While âą Try-Catch Example: see "if statement.." + nl x = 1 if x = 1 { see "one" + nl elseif x=2 see "two" + nl elseif x=3 see "three" + nl } see "for loop.." + nl for t = 1 to 10 { see t } see nl see "switch..." + nl x = 1 switch x { on 1 see "one" + nl on 2 see "two" + nl } see "try catch..." + nl try { 71.10. Using braces to start and end different control structures 822
- 5. Ring Documentation, Release 1.9 x = 1 / 0 catch see "catching error" + nl } Output: if statement.. one for loop.. 12345678910 switch... one try catch... catching error 71.11 Using âputâ and âgetâ as âseeâ and âgiveâ We can replace the âseeâ keyword with the âputâ keyword. Also we can replacew the âgiveâ keyword with the âgetâ keyword. Example: put "Hello World" + nl put "Enter Your Name ? " Get Name Put "Hello " + Name 71.12 Using âcaseâ as âonâ in switch statements We can replace the âonâ keyword with âcaseâ keyword in the switch statement. Example (1) : for x=1 to 10 switch x case 1 put "one" + nl case 2 put "two" + nl case 3 put "thre" + nl else put "else" + nl end end Example (2) : for x=1 to 10 { switch x { case 1 put "one" + nl case 2 put "two" + nl case 3 put "thre" + nl else put "else" + nl } } 71.11. Using âputâ and âgetâ as âseeâ and âgiveâ 823
- 6. Ring Documentation, Release 1.9 71.13 Using âdefâ as âfuncâ in functions/methods deïŹnition We can use the âdefâ keyword as the âfuncâ keyword to deïŹne functions and methods. Example: one() two() def one put "one" + nl def two put "two" + nl 71.14 Using braces { } in Packages/Classes/Functions Example: load "stdlib.ring" import mypackage new myclass { myfunc() } package mypackage { class myclass { func myfunc { print("Hello, World!n") } } } 71.15 Using âendâ keyword after Packages/Classes/Functions Example: import mypackage new myclass { myfunc() } package mypackage class myclass def myfunc put "Hello, World!" end end end 71.13. Using âdefâ as âfuncâ in functions/methods deïŹnition 824
- 7. Ring Documentation, Release 1.9 71.16 Using âendpackageâ/âendclassâ/âendfuncâ keywords after Pack- ages/Classes/Functions Example: import mypackage new myclass { myfunc() } package mypackage class myclass func myfunc see "welcome" + nl endfunc endclass endpackage 71.17 Ignore new lines after keywords Starting from Ring 1.8 the compiler will ignore new lines after keywords that expect tokens after it Example: see " Hello, World! " test() func #======================# Test #======================# ? " Hello from the Test function " Output: Hello, World! Hello from the Test function 71.16. Using âendpackageâ/âendclassâ/âendfuncâ keywords after Packages/Classes/Functions 825
- 8. CHAPTER SEVENTYTWO INTRODUCTION TO THE TYPE HINTS LIBRARY In this chapter we will learn about the Type Hints Library 72.1 Why Type Hints? Using this library we can add the type information to the source code which will be very useful for tools like âą Code Editors âą Static-Analysis Note: Ring is a dynamic language, No type checking will be done by the compiler. 72.2 Example The next example will use the Type Hints library load "typehints.ring" see sum(3,4) + nl ; see sayHello("Mahmoud"); int func sum(int x,int y) { return x+y ; } string func sayHello(string name) { return "Hello " + name ; } 72.3 User Types The Type Hints library is very powerful and will support user types (Classes) automatically Example: load "typehints.ring" import mypackage 826
- 9. Ring Documentation, Release 1.9 test() { main([:one,:two,:three]) } myclass func test() { see "Testing User Types!" + nl return new myclass } package mypackage { public class myclass { public static void func main(list args) { see "welcome" + nl see args } } } 72.4 Using Types inside Code Also you can use the types inside the code (not only the function prototype) Example: load "typehints.ring" int sum = sum(3,4) string msg = sayHello("Mahmoud") see "Sum = " + sum + nl + msg + nl int func sum(int x,int y) { return x+y ; } string func sayHello(string name) { return "Hello " + name ; } 72.5 Rules âą To use the types in the function prototype you must use â(â and â)â around parameters âą To use the types in the function code, You must set the variable value (Assignment). The next types are deïŹned by the library # Low Level Types char unsigned signed int short long float 72.4. Using Types inside Code 827
- 10. Ring Documentation, Release 1.9 double void # High Level Types string list number object # Other public static abstract protected override 72.5. Rules 828