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cookbooks:devel:core [2020/11/11 09:37] miconda [loadpath] |
cookbooks:devel:core [2020/11/19 16:38] miconda [subst] |
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* text on the same line as the directive will cause problems. Keep the directive lines clean and only comment on a line before or after. | * text on the same line as the directive will cause problems. Keep the directive lines clean and only comment on a line before or after. | ||
+ | ==== defenv ==== | ||
+ | |||
+ | Preprocessor directive to define an ID to the value of an environment variable with the name ENVVAR. | ||
+ | |||
+ | <code c> | ||
+ | #!defenv ID=ENVVAR | ||
+ | </ | ||
+ | |||
+ | It can also be just **$!defenv ENVVAR** and the defined ID is the ENVVAR name. | ||
+ | |||
+ | Example: | ||
+ | |||
+ | <code c> | ||
+ | #!defenv SHELL | ||
+ | </ | ||
+ | |||
+ | If environment variable $SHELL is '/ | ||
+ | |||
+ | <code c> | ||
+ | #!define SHELL /bin/bash | ||
+ | </ | ||
+ | |||
+ | Full expression variant: | ||
+ | |||
+ | <code c> | ||
+ | #!defenv ENVSHELL=SHELL | ||
+ | </ | ||
+ | |||
+ | Then it is like: | ||
+ | |||
+ | <code c> | ||
+ | #!define ENVSHELL /bin/bash | ||
+ | </ | ||
+ | |||
+ | It is a simplified alternative of using **# | ||
+ | | ||
==== subst ==== | ==== subst ==== | ||