Make target substitution

Question

It seems that the subshell does not retrieve the result of "$@", so there is nothing to do substitution on.

%_bust.css: %.css
    @echo $(echo $@ | sed s/_bust/$(BUSTER)/g)

score 4 · Answer 1 · answered Feb 22 '12 at 09:52

4

Replace $() with ``. The former is GNU make variable expansion.

answered Feb 22 '12 at 09:52

Maxim Egorushkin

2

Or double any dollar sign you want to expose to the shell – tripleee Feb 22 '12 at 10:01

score 1 · Answer 2 · answered Feb 22 '12 at 15:42

1

You've made it unnecessarily complicated. You don't need a nested echo.

%_bust.css: %.css
    @echo $@ | sed s/_bust/$(BUSTER)/g

answered Feb 22 '12 at 15:42

Beta

score 0 · Answer 3 · answered Feb 22 '12 at 09:58

0

You could also use make's text subsitution mechanisms.

@echo $*$(BUSTER).css
@echo $(subst _bust,$(BUSTER),$@)

The latter is specific to GNU Make, and less precise and elegant in this particular case.

answered Feb 22 '12 at 09:58

tripleee

3 Answers3