The Ring programming language version 1.10 book - Part 126 of 212
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The document summarizes Ring functions for string manipulation. It provides the syntax, description, arguments, and return values for over 30 functions, including frAbs(), frAt(), frChr(), frEmpty(), frFile(), frLen(), frLTrim(), frPadL(), frProper(), frReplicate(), frRTrim(), frSpace(), frStr(), frStrTran(), and frSubStr(). These functions allow manipulating different parts of strings, padding strings, searching strings, and converting between strings and other data types.
The Ring programming language version 1.10 book - Part 126 of 212
- 1. Ring Documentation, Release 1.10 Table 91.1 – continued from previous page Function Name Description frListToString() Creates a string with the string elements of an Array. frLTrim() Removes all leading spaces or parsing characters from the specified character expression. frPadL() Returns a string from an expression, padded with spaces or characters to a specified length on the left side. frPadR() Returns a string from an expression, padded with spaces or characters to a specified length on the right side. frProper() Returns from a character expression a string capitalized as appropriate for proper names. frReplicate() Returns a character string that contains a specified character expression repeated a specified number of times. frRTrim() Removes all trailing spaces or parsing characters from the specified character expression. frSetIfEmpty() Set a Value into a variable if the variable value is empty, null or zero. frSetSeparatorTo() Specifies the character for the numeric place separator. frSpace() Returns a character string composed of a specified number of spaces. frStr() Returns the character equivalent of a numeric expression. frStringToList() Creates a List with the content of the specified string. frStrTran() Searches a character expression for a second character expression and replaces each occurrence with a third character expression. frStuff() Returns a new character string replaced by a specified number of characteres in a character expression with another character expression. frSubStr() Returns a character string from the given character expression, starting at a specified position in the character expression and continuing for a specified number of characters. frTransform() Returns a character string from an expression in a format determined by a format code. frVal() Returns a numeric value from a character expression composed of numbers. frVarType() Returns the data type of an expression. 91.2 frAbs() function * Syntax : lnReturnValue = frAbs(tnExpression) * Description : Returns the absolute value of the specified numeric expression. * : * Arguments : <tnExpression> * : Specifies the numeric expression whose absolute value frAbs() * : returns. * Returns : <lnReturnValue> * : Returns the absolute value of the specified numeric expression. 91.3 frAsc() function * Syntax : lnReturnValue = frAsc(tcExpression) * Description : Returns the ANSI value for the leftmost character in * : a character expression. * Arguments : <tcExpression> * : Specifies the character expression containing the character 91.2. frAbs() function 1218
- 2. Ring Documentation, Release 1.10 * : whose ANSI value frAsc() * : returns. Any characters after the first character in * : tcExpression are ignored by frAsc(). * Returns : <lnReturnValue> * : returns the position of the character in the character * : table of the current code page. * : Every character has a unique ANSI value in the * : range from 0 to 255. 91.4 frAddBs() function * Syntax : lcReturnValue = frAddBs(tcPath) * Description : Adds a backslash (if needed) to a path expression. * : * Arguments : <tcPath> * : Specifies the path name to which to add the backslash. * : * Returns : <lcReturnValue> The path with the backslash. 91.5 frAt() function * Syntax : lnPos = frAt(tcToSearch, tcString, tnOccurrence) * Description : Searches a character expression for the occurrence of * : another character expression. * : The search performed by frAt() is case-sensitive. * : * Arguments : <tcToSearch> * : Specifies the character expression to search * : for in <tcString>. * : <tcString> * : Specifies the character expression to search * : for <tcToSearch>. * : <tnOccurrence> * : Specifies which occurrence, first, second, third, * : and so on, of <tcToSearch> to search for * : in <tcString>. * : By default, frAt() searches for the first occurrence * : of <tcToSearch> (tnOccurrence = 1). * Returns : Numeric. frAt() returns an integer indicating the * : position of the first character for a * : character expression or memo field within another * : character expression or memo field, * : beginning from the leftmost character. If the * : expression or field is not found, or if * : <tnOccurrence> is greater than the number of * : times <tcToSearch> occurs in <tcString>, frAt() * : returns 0. 91.4. frAddBs() function 1219
- 3. Ring Documentation, Release 1.10 91.6 frAtC() function * Syntax : lnPos = frAtC(tcToSearch, tcString, tnOccurrence) * Description : Searches a character expression for the occurrence * : of another character expression * : without regard for the case of these two expressions. * : * Arguments : <tcToSearch> * : Specifies the character expression to search * : for in <tcString>. * : <tcString> * : Specifies the character expression to search * : for <tcToSearch>. * : <tnOccurrence> * : Specifies which occurrence, first, second, third, * : and so on, of <tcToSearch> to search for * : in tcString. * : By default, frAtC() searches for the first occurrence * : of <tcToSearch> (tnOccurrence = 1). * Returns : Numeric. frAtC() returns an integer indicating the * : position of the first character for a * : character expression or memo field within * : another character expression or memo field, * : beginning from the leftmost character. If the * : expression or field is not found, or if * : <tnOccurrence> is greater than the number of * : times <tcToSearch> occurs in <tcString>, frAtC() * : returns 0. 91.7 frChr() function * Syntax : lcReturnValue = frChr(tnExpression) * Description : Returns the character associated with the specified numeric * : ANSI code. * Arguments : <tnExpression> * : Specifies a number between 0 and 255 whose equivalent ANSI * : character frChr() returns. * Returns : <lcReturnValue> * : Returns a single character corresponding to the numeric * : position of the character in the * : character table of the current code page. * : * Remarks : tnExpression must be between 0 and 255 91.8 frEmpty() function * Syntax : llReturnValue = frEmpty(tuExpression) * Description : Determines whether an expression evaluates to empty. * : * Arguments : <tuExpression> * : Specifies the expression that EMPTY() evaluates. * : You can specify an expression with Character, * : Numeric, or logical type. 91.6. frAtC() function 1220
- 4. Ring Documentation, Release 1.10 * : * Returns : <llReturnValue> Logical 91.9 frFile() function * Syntax : llReturnValue = frFile(tcFileName, tnFlag) * Description : Checks if the specified file exists on disk. * : * Arguments : <tcFileName> * : Specifies the name of the file to check. * : tcFileName must include * : the file extension. You can include a path with * : the file name to * : search for a file in a directory or on a drive * : other than the current directory or drive. * : * : <tnFlag> * : tnFlag was included for future compatibility. * : In this version, It always returns true whenever * : the file exists on disk. * Returns : <llReturnValue> Logical * : True if file exists on disk. * : False if file doesn't exist on disk. 91.10 frFileToStr() function * Syntax : lcReturnValue = frFileToStr(tcFileName) * Description : Returns the contents of a file as a character string. * : * Arguments : <tcFileName> * : Specifies the name of the file whose contents are * : returned as a character * : string. If the file is in a directory other than * : the current default directory, * : include a path with the file name. * : * Returns : <lcReturnValue> * : A character string with the content of the specified file. * : 91.11 frStr() function * Syntax : lcReturnValue = frStr(tnValue, tnLen, tnDec) * Description : Returns the character equivalent of a numeric expression. * : * Arguments : <tnValue> * : Specifies the numeric expression to evaluate. * : * : <tnLen> * : Specifies the length of the character string returned. * : If tnLen is 0, tnLen defaults to 10 characters. 91.9. frFile() function 1221
- 5. Ring Documentation, Release 1.10 * : If tnLen < 0 returns one string with same length as the number. * : Note * : If the expression contains a decimal point, * : the length includes one character for * : the decimal point and one character * : for each digit in the character string. * : * : <tnDec> * : Specifies the number of decimal places in the * : character string returned. * : To specify the number of decimal places using * : tnDec, you must include nLength. If nDecimalPlaces is omitted, * : the number of decimal places defaults to zero (0). * : * Returns : Character data type. frStr() returns a character string * : equivalent to the specified numeric expression. * : Depending on certain conditions, frStr() can return the following: * : If you specify fewer decimal places than exist in tnValue, * : the return value is rounded up. To round results to the nearest * : decimal place instead of upward, include the ROUND( ) function. * : For more information, see ROUND( ) Function. * : If nExpression is an integer, and nLength is less than * : the number of digits in nExpression, frStr( ) returns a string of * : asterisks, indicating numeric overflow. * : If nExpression contains a decimal point, and nLength is equal * : to or less than the number of digits to the left of the decimal * : point, frStr( ) returns a string of asterisks, * : indicating numeric overflow. * : If nLength is greater than the length of the value evaluated * : by nExpression, frStr( ) returns a character string padded with * : leading spaces. * : If nExpression has Numeric or Float type, and nLength * : is less than the number of digits in nExpression, and , frStr( ) * : returns a value using scientific notation. 91.12 frSetIfEmpty() function * Syntax : tuReturnValue = frSetIfEmpty(tuValue, tuNewValue) * Description : Set a Value into a variable if the variable * : value is empty, null or zero. * Arguments : <tuValue> * : The value to evaluate. * : * : <tuNewValue> * : The value to set if tuValue is empty. * : * Returns : tuNewValue if tuValue is empty, otherwise * : returns the original value. * Remarks : This function doesn't exist in VFP. 91.12. frSetIfEmpty() function 1222
- 6. Ring Documentation, Release 1.10 91.13 frSpace() function * Syntax : lcReturnValue = frSpace(tnSpaces) * Description : Returns a character string composed of a * : specified number of spaces. * Arguments : <tnSpaces> * : Specifies the number of spaces that frSpace() returns. * : * Returns : <lcReturnValue> * : Character 91.14 frInList() function * Syntax : llReturnValue = frInList(tuExpression, taList) * Description : Determines whether an expression matches another * : expression in a set of expressions. * Arguments : <tuExpression> * : Specifies the expression frInList() searches for in the List. * : * : <taList> * : Specifies the List of expressions to search. * : You must include at least one element in the list. * : The expressions in the list of expressions needn't to be * : of the same data type. * : * Returns : <luReturnValue> Null or logical value. 91.15 frForcePath() function * Syntax : lcReturnValue = frForcePath(tcFileName, tcPath) * Description : Returns a file name with a new path name * : substituted for the old one. * Arguments : <tcFileName> * : Specifies the file name (with or without a path or extension), * : which will get a new path. * : <tcPath> * : Specifies the new path for tcFileName. * : * Returns : <lcReturnValue> * : Returns a file name with a new path name * : substituted for the old one. 91.16 frAllTrim() function Syntax : lcReturnValue = frAllTrim(tcExpression, tcCharacter) 91.13. frSpace() function 1223
- 7. Ring Documentation, Release 1.10 91.17 frLTrim() function Syntax : lcRet = frLTrim(tcExpression, tcCharacter) 91.18 frJustDrive() function * Syntax : lcReturnValue = frJustDrive(tcPath) * Description : Returns the drive letter from a complete path. * : * Arguments : <tcPath> * : Specifies the complete path name for * : which you want only the drive. * Returns : <lcReturnValue> * : Returns the drive letter from a complete path. 91.19 frJustExt() function * Syntax : lcReturnValue = frJustExt(tcPath) * Description : Returns the characters of a file extension * : from a complete path. * Arguments : <tcPath> * : Specifies the name, which may include the full path, * : of the file for which you want only the extension. * Returns : <lcReturnValue> * : Returns the drive characters of a file extension * : from a complete path. 91.20 frJustStem() function * Syntax : lcReturnValue = frJustStem(tcPath) * Description : Returns the stem name (the file name before the extension) * : from a complete path and file name. * Arguments : <tcPath> * : Specifies the name (including path) of the file * : for which you want only the stem. * Returns : <lcReturnValue> * : Returns the stem name of a file from a complete path. 91.21 frRTrim() function Syntax : lcRet = frRTrim(tcExpression, tcCharacter) 91.17. frLTrim() function 1224
- 8. Ring Documentation, Release 1.10 91.22 frJustPath() function Syntax : tcReturnValue = frJustPath(tcExpression) 91.23 frForceExt() function Syntax : tcReturnValue = frForceExt(tcFileName, tcNewExtension) 91.24 frALines() function Syntax : tnReturnValue = frALines(taList, tcExpression, tcSeparator) 91.25 frJustFName() function Syntax : tcReturnValue = frJustFName(tcExpression) 91.26 frPadL() function Syntax : tcReturnValue = frPadL(tcString, tnLen, tcChar) 91.27 frPadR() function Syntax : tcReturnValue = frPadR(tcString, tnLen, tcChar) 91.28 frProper() function * Syntax : tcReturnValue = frProper(tcExpression) * Description : Returns from a character expression a string * : capitalized as appropriate for proper names. * Arguments : <tcExpression> * : Specifies the character expression from which * : frProper() returns a capitalized character string. * Returns : <tcReturnValue> 91.29 frReplicate() function Syntax : tcReturnValue = frReplicate(tcString, tnTimes) 91.22. frJustPath() function 1225
- 9. Ring Documentation, Release 1.10 91.30 frLen() function Syntax : tnReturnValue = frLen(tcString) 91.31 frStuff() function * Syntax : tcReturnValue = frStuff(tcExpression, tnStartRep, tnCharRep, tcToReplace) * Description : Returns a new character string replaced by a * : specified number of characters in a character * : expression with another character expression. * : * Arguments : <tcExpression> * : Specify the character expression in which the replacement occurs. * : * : <tnStartRep> * : Specify the position in <tcExpression> where the replacement begins. * : * : <tnCharRep> * : Specifies the number of characters to be replaced. * : If <tnCharRep> is 0, the replacement string * : <tcToReplace> is inserted into <tcExpression>. * : * : <tcToReplace> * : Specifies the replacement character expression. * : If <tcToReplace> is an empty string, the number of * : characters specified by <tnCharRep> are removed from <tcExpression>. * : * Returns : Character 91.32 frSubStr() function Syntax : tcReturnValue = frSubStr(tcString, tnInitialPosition, tnNumberBytes) 91.33 frStrTran() function Syntax : tcReturnValue = frStrTran(tcString, tcOldString, tcNewString) 91.34 frListToString() function * Syntax : lcRet = frListToString(taList) * Remarks : This function doesn't exist in VFP. 91.30. frLen() function 1226
- 10. Ring Documentation, Release 1.10 91.35 frInt() function Syntax : lnInt = frInt(tnExpression) 91.36 frStringToList() function * Syntax : laList = frStringToList(tcExpression) * Remarks : This function doesn't exist in VFP. 91.37 frIIf() function * Syntax : luReturnValue = frIIf(tlExpression, tuReturnIfTrue, tuReturnIfFalse) * Description : Returns one of two values depending on the * : value of a logical expression. * Arguments : <tlExpression> * : Specifies the logical expression that frIIf() evaluates. * : * : <tuReturnTrue>, <tuReturnFalse> * : If tlExpression evaluates to True, tuReturnIfTrue is * : returned and tuReturnIfFalse is not evaluated. * : If tlExpression evaluates to False or Null, tuReturnIfFalse is * : returned and tuReturnIfTrue is not evaluated. * : * Returns : <luReturnValue> Defined by <tuReturnIfTrue> or <tuReturnIfFalse> 91.38 frVal() function * Syntax : luReturnValue = frVal(tcExpression) * Description : Returns a numeric value from a character expression * : composed of numbers * Arguments : <tcExpression> * : Specifies a character expression composed of up to 16 numbers. * : * Returns : <tnValue> * : Return a numeric value. 91.39 frBetween() function * Syntax : luReturnValue = frBetween(tuTestValue, tuLowValue, tuHighValue) * Description : Determines whether the value of an expression * : is inclusively between the * : values of two expressions of the same type. * : * Arguments : <tuTestValue> * : Specifies an expression to evaluate. * : * : <tuLowValue> * : Specifies the lower value in the range. 91.35. frInt() function 1227