Creates a Makefile rule


make_rule(targets, deps = NULL, script = NULL)


[character] Target names
[character] Dependency names
[character] A script to execute to build the targets.


An object of class MakefileR_rule


A rule in a Makefile consists of a (list of) targets which may depend on one or more dependencies each. Optionally, a script is executed to create the target. Generally, multiple targets mean that the rule is identical for each of the individual targets, and multiple dependencies mean that all of them are required to build each of the targets. In the script, the target can be referenced by $@, and the first dependency can be referenced by $<. Note that the dollar sign has a special meaning in a Makefile, use $$ in scripts that need to use the dollar sign themselves.


Use the c function or the + operator to append rules to groups and Makefiles.


make_rule("all", c("first_target", "second_target"))
all: first_target second_target
make_rule("first_target", ".FORCE", "echo 'Building first target'")
first_target: .FORCE echo 'Building first target'
make_rule("second_target", "first_target", c("echo 'Building second target'", "echo 'Done'"))
second_target: first_target echo 'Building second target' echo 'Done'
makefile() + make_rule("all", c("first_target", "second_target")) + make_rule(".FORCE") + make_rule("first_target", ".FORCE", "echo 'Building first target'") + make_rule("second_target", "first_target", c("echo 'Building second target'", "echo 'Done'"))
# Generated by MakefileR, do not edit by hand all: first_target second_target .FORCE: first_target: .FORCE echo 'Building first target' second_target: first_target echo 'Building second target' echo 'Done'