Remove item from a Makefile variable?
I have a makefile, which includes several other makefiles, which in turn all add to a variable like this:
VAR := Something SomethingElse
VAR += SomeOtherThing
(...)
Now I wish to remove SomethingElse
from the VAR
variable. What do I put in place of (...)
to do this?
I am usin开发者_如何学Gog GNU Make, and a GNU Make specific solution will be fine.
You could use the filter-out
text function if you're using GNU Make.
OTHERVAR := $(filter-out SomethingElse,$(VAR))
On top of the correct answer above:
VAR = bla1 bla2 bla3 bla4 bla5
TMPVAR := $(VAR)
VAR = $(filter-out bla3, $(TMPVAR))
all:
@echo "VAR is: $(VAR)"
Output:
VAR is: bla1 bla2 bla4 bla5
Note that this breaks all "recursivity" when filter-out is executed, but that might not matter in your case.
As I also have a similar situation, I want to add a new answer. In my case there were also commas into the variable string and, more, I wanted to remove the comma and the last word :
VAR = "bla1, bla2"
In this case filter out is not working (not even in the previous answers, when there are no quotes)
My solution is to use subst
:
VAR = "bla1, bla2"
TTT = , bla2
TMPVAR := $(VAR)
SUBST = $(subst $(TTT),, $(TMPVAR))
FILT = $(filter-out $(TTT), $(TMPVAR))
subst:
@echo "subst : $(SUBST)"
filter:
@echo "filter-out : $(FILT)"
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