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29 lines
1.3 KiB
Plaintext
29 lines
1.3 KiB
Plaintext
[[$LET]] is a precompiler command, which is now usable by modern day [[cavemen]] to help include and exclude which sections of code compiles in their program based on OS/bit-size or other predefined conditions.
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{{PageSyntax}}
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: [[$LET]] variable = expression
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{{PageDescription}}
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* Unlike [[LET]], [[$LET]] is not optional.
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* $LET a = 12 sets a precompiler variable "a" to the value of 12. This variable is only valid for the precompiler itself and does nothing to affect the values of any variable/constant which might also be called "a" in the program.
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* Variable names can contain numbers, letters, and periods in any order. [[$LET]] '''3.2 = TRUE''' is a perfectly valid variable and expression.
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* Expressions can contain one set of leading and/or trailing quotes; and any number of numbers, letters, and periods, in any order. [[$LET]] '''3.2 = "TRUE"''' is also perfectly valid, but [[$LET]] '''3.2 = ""TRUE""''' will error because of the double quotes.
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* You can check a precompiler variable against special values '''DEFINED''' and '''UNDEFINED''', in order to assess whether the variable has already been assigned a value. Useful for code in libraries which may be repeated.
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{{PageExamples}}
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* See example 1 in [[$IF]].
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{{PageSeeAlso}}
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* [[$IF]]
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* [[$ELSE]]
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* [[$ELSEIF]]
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* [[$END IF]]
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* [[Cavemen]]
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{{PageNavigation}}
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