-## ------------------ ##
-## Decoding options. ##
-## ------------------ ##
-
-# b4_flag_if(FLAG, IF-TRUE, IF-FALSE)
-# -----------------------------------
-# Run IF-TRUE if b4_FLAG_flag is 1, IF-FALSE if FLAG is 0, otherwise fail.
-m4_define([b4_flag_if],
-[m4_case(b4_$1_flag,
- [0], [$3],
- [1], [$2],
- [m4_fatal([invalid $1 value: ]$1)])])
-
-
-# b4_define_flag_if(FLAG)
-# -----------------------
-# Define "b4_FLAG_if(IF-TRUE, IF-FALSE)" that depends on the
-# value of the Boolean FLAG.
-m4_define([b4_define_flag_if],
-[_b4_define_flag_if($[1], $[2], [$1])])
-
-# _b4_define_flag_if($1, $2, FLAG)
-# --------------------------------
-# This macro works around the impossibility to define macros
-# inside macros, because issuing `[$1]' is not possible in M4 :(.
-# This sucks hard, GNU M4 should really provide M5 like $$1.
-m4_define([_b4_define_flag_if],
-[m4_if([$1$2], $[1]$[2], [],
- [m4_fatal([$0: Invalid arguments: $@])])dnl
-m4_define([b4_$3_if],
- [b4_flag_if([$3], [$1], [$2])])])
-
-
-# b4_FLAG_if(IF-TRUE, IF-FALSE)
-# -----------------------------
-# Expand IF-TRUE, if FLAG is true, IF-FALSE otherwise.
-b4_define_flag_if([defines]) # Whether headers are requested.
-b4_define_flag_if([error_verbose]) # Wheter error are verbose.
-b4_define_flag_if([locations]) # Whether locations are tracked.
-b4_define_flag_if([pure]) # Whether the interface is pure.
-