Example
Simply-expanded variables behave like variables from traditional programming languages. The expression on the right-hand side is evaluated, and the result is stored in the variable. If the right-hand side contains a variable reference, that variable is expanded before the assignment takes place.
x := hello
y := $(x)
# Both $(x) and $(y) will now yield "hello"
x := world
# $(x) will now yield "world", and $(y) will yield "hello"
An alternative form is to use double-colon assignment:
x ::= hello
Single- and double-colon assignment are equivalent. The POSIX make standard only mentions the ::= form, so implementations with strict standards compliance may not support the single-colon version.
