# Makefile.string
# author: byuu
# license: public domain

[A-Z] = A B C D E F G H I J K L M N O P Q R S T U V W X Y Z
[a-z] = a b c d e f g h i j k l m n o p q r s t u v w x y z
[0-9] = 0 1 2 3 4 5 6 7 8 9
[markup] = ` ~ ! @ \# $$ % ^ & * ( ) - _ = + [ { ] } \ | ; : ' " , < . > / ?
[all] = $([A-Z]) $([a-z]) $([0-9]) $([markup])
[space] := 
[space] +=

#####
# function strtr(source, from, to)
#####
strtr = \
  $(eval __temp := $1) \
  $(strip \
    $(foreach c, \
      $(join $(addsuffix :,$2),$3), \
      $(eval __temp := \
        $(subst $(word 1,$(subst :, ,$c)),$(word 2,$(subst :, ,$c)),$(__temp)) \
      ) \
    ) \
    $(__temp) \
  )

#####
# function strupper(source)
#####
strupper = $(call strtr,$1,$([a-z]),$([A-Z]))

#####
# function strlower(source)
#####
strlower = $(call strtr,$1,$([A-Z]),$([a-z]))

#####
# function strlen(source)
#####
strlen = \
  $(eval __temp := $(subst $([space]),_,$1)) \
  $(words \
    $(strip \
      $(foreach c, \
        $([all]), \
        $(eval __temp := \
          $(subst $c,$c ,$(__temp)) \
        ) \
      ) \
      $(__temp) \
    ) \
  )

#####
# function streq(source)
#####
streq = $(if $(filter-out xx,x$(subst $1,,$2)$(subst $2,,$1)x),,1)

#####
# function strne(source)
#####
strne = $(if $(filter-out xx,x$(subst $1,,$2)$(subst $2,,$1)x),1,)
