build: factor the LolFx compilation rule into configure.ac.

configure.ac

@@ -364,6 +364,11 @@ fi
 AM_CONDITIONAL(USE_GTKGL, test "${ac_cv_my_have_gtkgl}" != "no")
 
 
+dnl  LolFx compilation rule
+LOLFX_BUILD='(echo "char const *"; echo "lolfx_$(notdir $(basename $(filter %.lolfx, $^))) ="; $(SED) '"'"'s/"/\\"/g'"'"' $(filter %.lolfx, $^) | $(SED) '"'"'s/\([^\r]*\).*/"\1\\n"/'"'"'; echo ";") | $(CXXCOMPILE) -xc++ -c - -o $@'
+AC_SUBST(LOLFX_BUILD)
+
+
 dnl Extra libraries we may need
 AC_SUBST(MATH_LIBS)
 AC_SUBST(PAM_LIBS)

src/Makefile.am

@@ -64,11 +64,7 @@ liblol_a_CPPFLAGS = @LOL_CFLAGS@
 
 SUFFIXES = .lolfx
 .lolfx.o:
-	(echo "char const *"; \
-	 echo "lolfx_$(notdir $(basename $(filter %.lolfx, $^))) ="; \
-	 $(SED) 's/"/\\"/g' $(filter %.lolfx, $^) | \
-	 $(SED) 's/\([^\r]*\).*/"\1\\n"/'; \
-	 echo ";") | $(CXXCOMPILE) -xc++ -c - -o $@
+	$(LOLFX_BUILD)
 
 if TRUE
 generated: .FORCE

tutorial/Makefile.am

@@ -12,11 +12,7 @@ CLEANFILES = $(noinst_PROGRAMS:%$(EXEEXT)=%.self) \
 
 SUFFIXES = .lolfx
 .lolfx.o:
-	(echo "char const *"; \
-	 echo "lolfx_$(notdir $(basename $(filter %.lolfx, $^))) ="; \
-	 $(SED) 's/"/\\"/g' $(filter %.lolfx, $^) | \
-	 $(SED) 's/\([^\r]*\).*/"\1\\n"/'; \
-	 echo ";") | $(CXXCOMPILE) -xc++ -c - -o $@
+	$(LOLFX_BUILD)
 
 noinst_PROGRAMS = 01_triangle 02_cube 11_fractal