Inno Setup Preprocessor: TypeOf
Prototype
int TypeOf(<ident>)
int TypeOf <ident>
Description
Special function. It takes an identifier as opposed to an expression. Returns one of predefined values, each of which corresponds to a particular value type (void, integer, or string), if an identifier is a variable name, or identifier type (macro or function) otherwise. Values that this function returns are typically declared in ISPPBuiltins.iss file.
It is allowed to not use parentheses with this function.