lazy make vars assignment

Makefile

@@ -10,7 +10,7 @@ images:
 images/wide.jpg:| images
 	convert -size 100x60 xc:skyblue -fill white -stroke black  -draw "ellipse 50,30 40,20 45,270" images/wide.jpg
 
-ALL_FILES = $(wildcard *.tex) $(wildcard *.sty) | $(DROSS)
+ALL_FILES := $(wildcard *.tex) $(wildcard *.sty) | $(DROSS)
 
 $(DROSS)/test.pdf: test.tex $(ALL_FILES)
 	$(RUN) test.tex

vars

-CP = ln -f
-BOOK = $(shell basename "$$(pwd)")
-DROSS = $(shell head -1 .gitignore)
-COMPILER = latexmk -auxdir=$(DROSS) -pdflua -silent -shell-escape -r config/.latexmkrc -jobname=$(BOOK)
-GLOS = makeglossaries -d $(DROSS)
-RUN = lualatex -output-directory $(DROSS) -shell-escape
-QR_TARGET = $(shell grep 'mailto' README.md | cut -d' ' -f2)
-CLEAN = $(RM) -r $(DROSS) qr.tex *.pdf svg-inkscape
-DEPS = *tex config/*sty
+CP := ln -f
+BOOK := $(shell basename "$$(pwd)")
+DROSS := $(shell head -1 .gitignore)
+COMPILER := latexmk -auxdir=$(DROSS) -pdflua -silent -shell-escape -r config/.latexmkrc -jobname=$(BOOK)
+GLOS := makeglossaries -d $(DROSS)
+RUN := lualatex -output-directory $(DROSS) -shell-escape
+QR_TARGET := $(shell grep 'mailto' README.md | cut -d' ' -f2)
+CLEAN := $(RM) -r $(DROSS) qr.tex *.pdf svg-inkscape
+DEPS := *tex config/*sty