makefile: find a position of word in a variable

Question

In my makefile, I need to make a variable assignment based on a command line variable value. for example, I do:

make var_1=xxx

where

Answer 1

One way simulate associative containers in make is to use computed variables. E.g.:

var_2.a := A
var_2.b := B
# ...

# lookup
var_2 = ${var_2.${var_1}}
# or, lookup and assign a default value if lookup fails
var_2_or_default = $(or ${var_2.${var_1}},)