ThinBASIC Core Language > BuiltIn Functions > String functions

Description

The $ special character identifies a string literal as an interpolated string. An interpolated string is a string literal that might contain interpolation expressions. When an interpolated string is resolved to a result string, items with interpolation expressions are replaced by the string representations of the expression results.

Syntax

s = $(StringExpression [, ActivateRuntimeErrors [, sBlockLeftDelimiter [, sBlockRightDelimiter [, ReplaceSingleQuote]]]])

Returns

String

If an error will occur during any expression evaluation, an empty string will be returned

Parameters

Name	Type	Optional	Meaning
StringExpression	String	No	A string expression containing one or more interpolated strings to be interpreted as thinBasic string expression. Interpolated string must be included between { and } Single quote string: StringExpression can have single quote strings and they will be changed to double quote strings at runtime
ActivateRuntimeErrors	Number	Yes	By default $() will ignore run-time errors while interpreting interpolated expressions. Setting this optional parameter to %TRUE will generate a parsing error if one interpolated expression will generate e run-time error.
sBlockLeftDelimiter	String	Yes	By default left delimiter for interpolated strings is { You can change it passing your preferred delimiter
sBlockRightDelimiter	String	Yes	By default right delimiter for interpolated strings is } You can change it passing your preferred delimiter
ReplaceSingleQuote	Number	Yes	If %TRUE, single quote ' will be replaced by double quotes " inside single interpolated block string before it is resolved.

Remarks

The structure of an item with an interpolation expression is as follows: {interpolationExpression}

That is: a valid thinBasic expression between { and } delimiters.

{ and } delimiters can be changed passing personalized delimiters to $ function

Restrictions

{interpolationExpression} must contain a valid thinBasic expression in the running context and scope.

It can refer to local or global variables.

It can contains string and numeric expressions

It can contains any valid module functions active in current script.

IMPORTANT:

{interpolationExpression} is always interpreted as a string expression following all thinBasic rules of string expressions.

For example + sign is directly considered string concatenation and not sum of two expressions.

If you want execute math calculations include them into Str$() or Format$() or any other function that will return a string from a math expression

Example:

this will return "Value is 11"

printl $("Value is {1 + 1}")

this will return "Value is 2"

printl $("Value is {Format$(1 + 1)}")

IMPORTANT:

{interpolationExpression} cannot be recursive: it cannot contains another interpolation expression.

But StringExpression parameter can contains up to 1024 {interpolationExpression} non recursive expressions.

$() String Interpolation

$() String Interpolation