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How to create a macro with an argument?
1 Macros with arguments To create a macro with arguments, put them in parentheses separated by commas after the macro name, e.g. 2 Multiple macros One macro can expand to another; for example, after defining Toggle line numbers 1 #define FOO BAR 2 #define BAR (12) 3 it will be the case 3 Macro tricks 3.1.
Is it best to mark macro names by capitalization?
For this reason it is generally best to avoid side-effects in macro arguments, and to mark macro names (e.g. by capitalization) to clearly distinguish them from function names, where this issue doesn’t come up. 1.3. Variable-length argument lists
Which is more sophisticated assert or file macro?
The assert macro is a more sophisticated version, which uses the built-in macros __FILE__ (which expands to the current source file as a quoted string) and __LINE__ (which expands to the current source line number, not quoted) to not only print out an offending expression, but also the location of it in the source. 3.5. Big macros
Can a C preprocessor recognize a macro command?
The answer is no. C preprocessor commands are only recognized in unexpanded text. If you want self-modifying macros you will need to use a fancier macro processor like m4.
How to define a variadic macro in C99?
Variable-length argument lists C99 added variadic macros that may have a variable number of arguments; these are mostly useful for dealing with variadic functions (like printf) that also take a variable number of arguments. To define a variadic macro, define a macro with arguments where the last argument is three periods: .
When to use stringizing operator in macro definition?
If it precedes a formal parameter in the macro definition, the actual argument passed by the macro invocation is enclosed in quotation marks and treated as a string literal. The string literal then replaces each occurrence of a combination of the stringizing operator and formal parameter within the macro definition.
Can a SAS function take a character argument?
SAS says: ERROR: INPUT function requires a character argument. when I run the following code: I tried to have ‘&fyq0’ instead of &fyq0 as the 1st argument for the -input- function as the following: Then SAS says: NOTE: Invalid argument to function INPUT. Missing values may be generated.