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bmakelib.default-if-blank

If the given variable is blank, sets its value to the provided default.

Example 1

Makefile:

VAR1 =
VAR2 = 100
some-target : bmakelib.default-if-blank( VAR1,foo VAR2,bar )
    @echo 👉 VAR1=$(VAR1), VAR2=$(VAR2)

Shell:

$ make some-target
👉 VAR1=foo, VAR2=100

Example 2

Makefile:

some-target : bmakelib.default-if-blank( VAR1,foo )
    @echo ✅ VAR1 is $(VAR1)

Shell:

$ make bmakelib.conf.default-if-blank.SILENT=no some-target
Using default value 'foo' for variable 'VAR1'.
✅ VAR1 is foo

Notes:

  • Set bmakelib.conf.default-if-blank.SILENT to "no" to emit an info message when using the default value.

  • Currently there's no way to pass a value which contains spaces for a variable. That is, the following will have undesired effects:

some-target : bmakelib.default-if-blank( VAR1,hello world )

bmakelib.conf.default-if-blank.SILENT

Controls whether bmakelib.default-if-blank should emit an info message when using the default provided.

Precedence: 1. bmakelib.conf.default-if-blank.SILENT (Make variable) 2. BMAKELIB_CONF_DEFAULT_IF_BLANK_SILENT (environment variable) 3. yes (default)