--- /dev/null
+# ----------------------------------------------------------------------------
+#
+# GNU Make Standard Library (GMSL)
+#
+# A library of functions to be used with GNU Make's $(call) that
+# provides functionality not available in standard GNU Make.
+#
+# Copyright (c) 2005-2007 John Graham-Cumming
+#
+# This file is part of GMSL
+#
+# Redistribution and use in source and binary forms, with or without
+# modification, are permitted provided that the following conditions
+# are met:
+#
+# Redistributions of source code must retain the above copyright
+# notice, this list of conditions and the following disclaimer.
+#
+# Redistributions in binary form must reproduce the above copyright
+# notice, this list of conditions and the following disclaimer in the
+# documentation and/or other materials provided with the distribution.
+#
+# Neither the name of the John Graham-Cumming nor the names of its
+# contributors may be used to endorse or promote products derived from
+# this software without specific prior written permission.
+#
+# THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+# "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+# LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
+# FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
+# COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
+# INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
+# BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
+# LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
+# CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+# LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
+# ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+# POSSIBILITY OF SUCH DAMAGE.
+#
+# ----------------------------------------------------------------------------
+
+# This is the GNU Make Standard Library version number as a list with
+# three items: major, minor, revision
+
+gmsl_version := 1 0 9
+
+# Used to output warnings and error from the library, it's possible to
+# disable any warnings or errors by overriding these definitions
+# manually or by setting GMSL_NO_WARNINGS or GMSL_NO_ERRORS
+
+__gmsl_name := GNU Make Standard Library
+__gmsl_warning = $(warning $(__gmsl_name): $1)
+__gmsl_error = $(error $(__gmsl_name): $1)
+
+ifdef GMSL_NO_WARNINGS
+__gmsl_warning :=
+endif
+ifdef GMSL_NO_ERRORS
+__gmsl_error :=
+endif
+
+# If GMSL_TRACE is enabled then calls to the library functions are
+# traced to stdout using warning messages with their arguments
+
+ifdef GMSL_TRACE
+__gmsl_tr1 = $(warning $0('$1'))
+__gmsl_tr2 = $(warning $0('$1','$2'))
+__gmsl_tr3 = $(warning $0('$1','$2','$3'))
+else
+__gmsl_tr1 :=
+__gmsl_tr2 :=
+__gmsl_tr3 :=
+endif
+
+# Figure out whether we have $(eval) or not (GNU Make 3.80 and above)
+# if we do not then output a warning message, if we do then some
+# functions will be enabled.
+
+__gmsl_have_eval := $(false)
+__gmsl_ignore := $(eval __gmsl_have_eval := $(true))
+
+# See if we have $(lastword) (GNU Make 3.81 and above)
+
+__gmsl_have_lastword := $(lastword $(false) $(true))
+
+# See if we have native or and and (GNU Make 3.81 and above)
+
+__gmsl_have_or := $(if $(filter-out undefined, \
+ $(origin or)),$(call or,$(true),$(false)))
+__gmsl_have_and := $(if $(filter-out undefined, \
+ $(origin and)),$(call and,$(true),$(true)))
+
+ifneq ($(__gmsl_have_eval),$(true))
+$(call __gmsl_warning,GNU Make $(MAKE_VERSION) does not support $$(eval): some functions disabled)
+endif
+
+# ----------------------------------------------------------------------------
+# Function: gmsl_compatible
+# Arguments: List containing the desired library version number (maj min rev)
+# Returns: $(true) if this version of the library is compatible
+# with the requested version number, otherwise $(false)
+# ----------------------------------------------------------------------------
+gmsl_compatible = $(strip \
+ $(if $(call gt,$(word 1,$1),$(word 1,$(gmsl_version))), \
+ $(false), \
+ $(if $(call lt,$(word 1,$1),$(word 1,$(gmsl_version))), \
+ $(true), \
+ $(if $(call gt,$(word 2,$1),$(word 2,$(gmsl_version))), \
+ $(false), \
+ $(if $(call lt,$(word 2,$1),$(word 2,$(gmsl_version))), \
+ $(true), \
+ $(call lte,$(word 3,$1),$(word 3,$(gmsl_version))))))))
+
+# ###########################################################################
+# LOGICAL OPERATORS
+# ###########################################################################
+
+# not is defined in gmsl
+
+# ----------------------------------------------------------------------------
+# Function: and
+# Arguments: Two boolean values
+# Returns: Returns $(true) if both of the booleans are true
+# ----------------------------------------------------------------------------
+ifneq ($(__gmsl_have_and),$(true))
+and = $(__gmsl_tr2)$(if $1,$(if $2,$(true),$(false)),$(false))
+endif
+
+# ----------------------------------------------------------------------------
+# Function: or
+# Arguments: Two boolean values
+# Returns: Returns $(true) if either of the booleans is true
+# ----------------------------------------------------------------------------
+ifneq ($(__gmsl_have_or),$(true))
+or = $(__gmsl_tr2)$(if $1$2,$(true),$(false))
+endif
+
+# ----------------------------------------------------------------------------
+# Function: xor
+# Arguments: Two boolean values
+# Returns: Returns $(true) if exactly one of the booleans is true
+# ----------------------------------------------------------------------------
+xor = $(__gmsl_tr2)$(if $1,$(if $2,$(false),$(true)),$(if $2,$(true),$(false)))
+
+# ----------------------------------------------------------------------------
+# Function: nand
+# Arguments: Two boolean values
+# Returns: Returns value of 'not and'
+# ----------------------------------------------------------------------------
+nand = $(__gmsl_tr2)$(if $1,$(if $2,$(false),$(true)),$(true))
+
+# ----------------------------------------------------------------------------
+# Function: nor
+# Arguments: Two boolean values
+# Returns: Returns value of 'not or'
+# ----------------------------------------------------------------------------
+nor = $(__gmsl_tr2)$(if $1$2,$(false),$(true))
+
+# ----------------------------------------------------------------------------
+# Function: xnor
+# Arguments: Two boolean values
+# Returns: Returns value of 'not xor'
+# ----------------------------------------------------------------------------
+xnor =$(__gmsl_tr2)$(if $1,$(if $2,$(true),$(false)),$(if $2,$(false),$(true)))
+
+# ###########################################################################
+# LIST MANIPULATION FUNCTIONS
+# ###########################################################################
+
+# ----------------------------------------------------------------------------
+# Function: first (same as LISP's car, or head)
+# Arguments: 1: A list
+# Returns: Returns the first element of a list
+# ----------------------------------------------------------------------------
+first = $(__gmsl_tr1)$(firstword $1)
+
+# ----------------------------------------------------------------------------
+# Function: last
+# Arguments: 1: A list
+# Returns: Returns the last element of a list
+# ----------------------------------------------------------------------------
+ifeq ($(__gmsl_have_lastword),$(true))
+last = $(__gmsl_tr1)$(lastword $1)
+else
+last = $(__gmsl_tr1)$(if $1,$(word $(words $1),$1))
+endif
+
+# ----------------------------------------------------------------------------
+# Function: rest (same as LISP's cdr, or tail)
+# Arguments: 1: A list
+# Returns: Returns the list with the first element removed
+# ----------------------------------------------------------------------------
+rest = $(__gmsl_tr1)$(wordlist 2,$(words $1),$1)
+
+# ----------------------------------------------------------------------------
+# Function: chop
+# Arguments: 1: A list
+# Returns: Returns the list with the last element removed
+# ----------------------------------------------------------------------------
+chop = $(__gmsl_tr1)$(wordlist 2,$(words $1),x $1)
+
+# ----------------------------------------------------------------------------
+# Function: map
+# Arguments: 1: Name of function to $(call) for each element of list
+# 2: List to iterate over calling the function in 1
+# Returns: The list after calling the function on each element
+# ----------------------------------------------------------------------------
+map = $(__gmsl_tr2)$(strip $(foreach a,$2,$(call $1,$a)))
+
+# ----------------------------------------------------------------------------
+# Function: pairmap
+# Arguments: 1: Name of function to $(call) for each pair of elements
+# 2: List to iterate over calling the function in 1
+# 3: Second list to iterate over calling the function in 1
+# Returns: The list after calling the function on each pair of elements
+# ----------------------------------------------------------------------------
+pairmap = $(strip $(__gmsl_tr3)\
+ $(if $2$3,$(call $1,$(call first,$2),$(call first,$3)) \
+ $(call pairmap,$1,$(call rest,$2),$(call rest,$3))))
+
+# ----------------------------------------------------------------------------
+# Function: leq
+# Arguments: 1: A list to compare against...
+# 2: ...this list
+# Returns: Returns $(true) if the two lists are identical
+# ----------------------------------------------------------------------------
+leq = $(__gmsl_tr2)$(strip $(if $(call seq,$(words $1),$(words $2)), \
+ $(call __gmsl_list_equal,$1,$2),$(false)))
+
+__gmsl_list_equal = $(if $(strip $1), \
+ $(if $(call seq,$(call first,$1),$(call first,$2)), \
+ $(call __gmsl_list_equal, \
+ $(call rest,$1), \
+ $(call rest,$2)), \
+ $(false)), \
+ $(true))
+
+# ----------------------------------------------------------------------------
+# Function: lne
+# Arguments: 1: A list to compare against...
+# 2: ...this list
+# Returns: Returns $(true) if the two lists are different
+# ----------------------------------------------------------------------------
+lne = $(__gmsl_tr2)$(call not,$(call leq,$1,$2))
+
+# ----------------------------------------------------------------------------
+# Function: reverse
+# Arguments: 1: A list to reverse
+# Returns: The list with its elements in reverse order
+# ----------------------------------------------------------------------------
+reverse =$(__gmsl_tr1)$(strip $(if $1,$(call reverse,$(call rest,$1)) \
+ $(call first,$1)))
+
+# ----------------------------------------------------------------------------
+# Function: uniq
+# Arguments: 1: A list from which to remove repeated elements
+# Returns: The list with duplicate elements removed without reordering
+# ----------------------------------------------------------------------------
+uniq = $(strip $(__gmsl_tr1)$(if $1,$(call uniq,$(call chop,$1)) \
+ $(if $(filter $(call last,$1),$(call chop,$1)),,$(call last,$1))))
+
+# ----------------------------------------------------------------------------
+# Function: length
+# Arguments: 1: A list
+# Returns: The number of elements in the list
+# ----------------------------------------------------------------------------
+length = $(__gmsl_tr1)$(words $1)
+
+# ###########################################################################
+# STRING MANIPULATION FUNCTIONS
+# ###########################################################################
+
+# Helper function that translates any GNU Make 'true' value (i.e. a
+# non-empty string) to our $(true)
+
+__gmsl_make_bool = $(if $(strip $1),$(true),$(false))
+
+# ----------------------------------------------------------------------------
+# Function: seq
+# Arguments: 1: A string to compare against...
+# 2: ...this string
+# Returns: Returns $(true) if the two strings are identical
+# ----------------------------------------------------------------------------
+seq = $(__gmsl_tr2)$(if $(filter-out xx,x$(subst $1,,$2)$(subst $2,,$1)x),$(false),$(true))
+
+# ----------------------------------------------------------------------------
+# Function: sne
+# Arguments: 1: A string to compare against...
+# 2: ...this string
+# Returns: Returns $(true) if the two strings are not the same
+# ----------------------------------------------------------------------------
+sne = $(__gmsl_tr2)$(call not,$(call seq,$1,$2))
+
+# ----------------------------------------------------------------------------
+# Function: split
+# Arguments: 1: The character to split on
+# 2: A string to split
+# Returns: Splits a string into a list separated by spaces at the split
+# character in the first argument
+# ----------------------------------------------------------------------------
+split = $(__gmsl_tr2)$(strip $(subst $1, ,$2))
+
+# ----------------------------------------------------------------------------
+# Function: merge
+# Arguments: 1: The character to put between fields
+# 2: A list to merge into a string
+# Returns: Merges a list into a single string, list elements are separated
+# by the character in the first argument
+# ----------------------------------------------------------------------------
+merge = $(__gmsl_tr2)$(strip $(if $2, \
+ $(if $(call seq,1,$(words $2)), \
+ $2,$(call first,$2)$1$(call merge,$1,$(call rest,$2)))))
+
+ifdef __gmsl_have_eval
+# ----------------------------------------------------------------------------
+# Function: tr
+# Arguments: 1: The list of characters to translate from
+# 2: The list of characters to translate to
+# 3: The text to translate
+# Returns: Returns the text after translating characters
+# ----------------------------------------------------------------------------
+tr = $(__gmsl_tr3)$(strip $(eval __gmsl_t := $3) \
+ $(foreach c, \
+ $(join $(addsuffix :,$1),$2), \
+ $(eval __gmsl_t := \
+ $(subst $(word 1,$(subst :, ,$c)),$(word 2,$(subst :, ,$c)), \
+ $(__gmsl_t))))$(__gmsl_t))
+
+# Common character classes for use with the tr function. Each of
+# these is actually a variable declaration and must be wrapped with
+# $() or ${} to be used.
+
+[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 #
+[A-F] := A B C D E F #
+
+# ----------------------------------------------------------------------------
+# Function: uc
+# Arguments: 1: Text to upper case
+# Returns: Returns the text in upper case
+# ----------------------------------------------------------------------------
+uc = $(__gmsl_tr1)$(call tr,$([a-z]),$([A-Z]),$1)
+
+# ----------------------------------------------------------------------------
+# Function: lc
+# Arguments: 1: Text to lower case
+# Returns: Returns the text in lower case
+# ----------------------------------------------------------------------------
+lc = $(__gmsl_tr1)$(call tr,$([A-Z]),$([a-z]),$1)
+
+# ----------------------------------------------------------------------------
+# Function: strlen
+# Arguments: 1: A string
+# Returns: Returns the length of the string
+# ----------------------------------------------------------------------------
+__gmsl_characters := 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
+__gmsl_characters += a b c d e f g h i j k l m n o p q r s t u v w y z
+__gmsl_characters += 0 1 2 3 4 5 6 7 8 9
+__gmsl_characters += ` ~ ! @ \# $$ % ^ & * ( ) - _ = +
+__gmsl_characters += { } [ ] \ : ; ' " < > , . / ? |
+
+# Aside: if you read the above you might think that the lower-case
+# letter x is missing, and that that's an error. It is missing, but
+# it's not an error. __gmsl_characters is used by the strlen
+# function. strlen works by transforming every character and space
+# into the letter x and then counting the x's. Since there's no need
+# to transform x into x I omitted it.
+
+# This results in __gmsl_space containing just a space
+
+__gmsl_space :=
+__gmsl_space +=
+
+strlen = $(strip $(eval __temp := $(subst $(__gmsl_space),x,$1))$(foreach a,$(__gmsl_characters),$(eval __temp := $$(subst $$a,x,$(__temp))))$(eval __temp := $(subst x,x ,$(__temp)))$(words $(__temp)))
+
+# This results in __gmsl_newline containing just a newline
+
+define __gmsl_newline
+
+
+endef
+
+# This results in __gmsl_tab containing a tab
+
+__gmsl_tab := #
+
+# ----------------------------------------------------------------------------
+# Function: substr
+# Arguments: 1: A string
+# 2: Start position (first character is 1)
+# 3: End position (inclusive)
+# Returns: A substring.
+# Note: The string in $1 must not contain a §
+# ----------------------------------------------------------------------------
+
+substr = $(strip $(eval __temp := $$(subst $$(__gmsl_space),§ ,$$1))$(foreach a,$(__gmsl_characters),$(eval __temp := $$(subst $$a,$$a$$(__gmsl_space),$(__temp))))$(eval __temp := $(wordlist $2,$3,$(__temp))))$(subst §,$(__gmsl_space),$(subst $(__gmsl_space),,$(__temp)))
+
+endif # __gmsl_have_eval
+
+# ###########################################################################
+# SET MANIPULATION FUNCTIONS
+# ###########################################################################
+
+# Sets are represented by sorted, deduplicated lists. To create a set
+# from a list use set_create, or start with the empty_set and
+# set_insert individual elements
+
+# This is the empty set
+empty_set :=
+
+# ----------------------------------------------------------------------------
+# Function: set_create
+# Arguments: 1: A list of set elements
+# Returns: Returns the newly created set
+# ----------------------------------------------------------------------------
+set_create = $(__gmsl_tr1)$(sort $1)
+
+# ----------------------------------------------------------------------------
+# Function: set_insert
+# Arguments: 1: A single element to add to a set
+# 2: A set
+# Returns: Returns the set with the element added
+# ----------------------------------------------------------------------------
+set_insert = $(__gmsl_tr2)$(sort $1 $2)
+
+# ----------------------------------------------------------------------------
+# Function: set_remove
+# Arguments: 1: A single element to remove from a set
+# 2: A set
+# Returns: Returns the set with the element removed
+# ----------------------------------------------------------------------------
+set_remove = $(__gmsl_tr2)$(filter-out $1,$2)
+
+# ----------------------------------------------------------------------------
+# Function: set_is_member
+# Arguments: 1: A single element
+# 2: A set
+# Returns: Returns $(true) if the element is in the set
+# ----------------------------------------------------------------------------
+set_is_member = $(if $(filter $1,$2),$(true),$(false))
+
+# ----------------------------------------------------------------------------
+# Function: set_union
+# Arguments: 1: A set
+# 2: Another set
+# Returns: Returns the union of the two sets
+# ----------------------------------------------------------------------------
+set_union = $(sort $1 $2)
+
+# ----------------------------------------------------------------------------
+# Function: set_intersection
+# Arguments: 1: A set
+# 2: Another set
+# Returns: Returns the intersection of the two sets
+# ----------------------------------------------------------------------------
+set_intersection = $(filter $1,$2)
+
+# ----------------------------------------------------------------------------
+# Function: set_is_subset
+# Arguments: 1: A set
+# 2: Another set
+# Returns: Returns $(true) if the first set is a subset of the second
+# ----------------------------------------------------------------------------
+set_is_subset = $(call set_equal,$(call set_intersection,$1,$2),$1)
+
+# ----------------------------------------------------------------------------
+# Function: set_equal
+# Arguments: 1: A set
+# 2: Another set
+# Returns: Returns $(true) if the two sets are identical
+# ----------------------------------------------------------------------------
+set_equal = $(call seq,$1,$2)
+
+# ###########################################################################
+# ARITHMETIC LIBRARY
+# ###########################################################################
+
+# Integers a represented by lists with the equivalent number of x's.
+# For example the number 4 is x x x x. The maximum integer that the
+# library can handle as _input_ is __gmsl_input_int which is defined
+# here as 65536
+
+__gmsl_sixteen := x x x x x x x x x x x x x x x x
+__gmsl_input_int := $(foreach a,$(__gmsl_sixteen), \
+ $(foreach b,$(__gmsl_sixteen), \
+ $(foreach c,$(__gmsl_sixteen), \
+ $(__gmsl_sixteen)))))
+
+# ----------------------------------------------------------------------------
+# Function: int_decode
+# Arguments: 1: A number of x's representation
+# Returns: Returns the integer for human consumption that is represented
+# by the string of x's
+# ----------------------------------------------------------------------------
+int_decode = $(__gmsl_tr1)$(words $1)
+
+# ----------------------------------------------------------------------------
+# Function: int_encode
+# Arguments: 1: A number in human-readable integer form
+# Returns: Returns the integer encoded as a string of x's
+# ----------------------------------------------------------------------------
+int_encode = $(__gmsl_tr1)$(wordlist 1,$1,$(__gmsl_input_int))
+
+# The arithmetic library functions come in two forms: one form of each
+# function takes integers as arguments and the other form takes the
+# encoded form (x's created by a call to int_encode). For example,
+# there are two plus functions:
+#
+# plus Called with integer arguments and returns an integer
+# int_plus Called with encoded arguments and returns an encoded result
+#
+# plus will be slower than int_plus because its arguments and result
+# have to be translated between the x's format and integers. If doing
+# a complex calculation use the int_* forms with a single encoding of
+# inputs and single decoding of the output. For simple calculations
+# the direct forms can be used.
+
+# Helper function used to wrap an int_* function into a function that
+# takes a pair of integers, perhaps a function and returns an integer
+# result
+__gmsl_int_wrap = $(call int_decode,$(call $1,$(call int_encode,$2),$(call int_encode,$3)))
+__gmsl_int_wrap1 = $(call int_decode,$(call $1,$(call int_encode,$2)))
+__gmsl_int_wrap2 = $(call $1,$(call int_encode,$2),$(call int_encode,$3))
+
+# ----------------------------------------------------------------------------
+# Function: int_plus
+# Arguments: 1: A number in x's representation
+# 2: Another number in x's represntation
+# Returns: Returns the sum of the two numbers in x's representation
+# ----------------------------------------------------------------------------
+int_plus = $(strip $(__gmsl_tr2)$1 $2)
+
+# ----------------------------------------------------------------------------
+# Function: plus (wrapped version of int_plus)
+# Arguments: 1: An integer
+# 2: Another integer
+# Returns: Returns the sum of the two integers
+# ----------------------------------------------------------------------------
+plus = $(__gmsl_tr2)$(call __gmsl_int_wrap,int_plus,$1,$2)
+
+# ----------------------------------------------------------------------------
+# Function: int_subtract
+# Arguments: 1: A number in x's representation
+# 2: Another number in x's represntation
+# Returns: Returns the difference of the two numbers in x's representation,
+# or outputs an error on a numeric underflow
+# ----------------------------------------------------------------------------
+int_subtract = $(strip $(__gmsl_tr2)$(if $(call int_gte,$1,$2), \
+ $(filter-out xx,$(join $1,$2)), \
+ $(call __gmsl_warning,Subtraction underflow)))
+
+# ----------------------------------------------------------------------------
+# Function: subtract (wrapped version of int_subtract)
+# Arguments: 1: An integer
+# 2: Another integer
+# Returns: Returns the difference of the two integers,
+# or outputs an error on a numeric underflow
+# ----------------------------------------------------------------------------
+subtract = $(__gmsl_tr2)$(call __gmsl_int_wrap,int_subtract,$1,$2)
+
+# ----------------------------------------------------------------------------
+# Function: int_multiply
+# Arguments: 1: A number in x's representation
+# 2: Another number in x's represntation
+# Returns: Returns the product of the two numbers in x's representation
+# ----------------------------------------------------------------------------
+int_multiply = $(strip $(__gmsl_tr2)$(foreach a,$1,$2))
+
+# ----------------------------------------------------------------------------
+# Function: multiply (wrapped version of int_multiply)
+# Arguments: 1: An integer
+# 2: Another integer
+# Returns: Returns the product of the two integers
+# ----------------------------------------------------------------------------
+multiply = $(__gmsl_tr2)$(call __gmsl_int_wrap,int_multiply,$1,$2)
+
+# ----------------------------------------------------------------------------
+# Function: int_divide
+# Arguments: 1: A number in x's representation
+# 2: Another number in x's represntation
+# Returns: Returns the result of integer division of argument 1 divided
+# by argument 2 in x's representation
+# ----------------------------------------------------------------------------
+int_divide = $(__gmsl_tr2)$(strip $(if $2, \
+ $(if $(call int_gte,$1,$2), \
+ x $(call int_divide,$(call int_subtract,$1,$2),$2),), \
+ $(call __gmsl_error,Division by zero)))
+
+# ----------------------------------------------------------------------------
+# Function: divide (wrapped version of int_divide)
+# Arguments: 1: An integer
+# 2: Another integer
+# Returns: Returns the integer division of the first argument by the second
+# ----------------------------------------------------------------------------
+divide = $(__gmsl_tr2)$(call __gmsl_int_wrap,int_divide,$1,$2)
+
+# ----------------------------------------------------------------------------
+# Function: int_max, int_min
+# Arguments: 1: A number in x's representation
+# 2: Another number in x's represntation
+# Returns: Returns the maximum or minimum of its arguments in x's
+# representation
+# ----------------------------------------------------------------------------
+int_max = $(__gmsl_tr2)$(subst xx,x,$(join $1,$2))
+int_min = $(__gmsl_tr2)$(subst xx,x,$(filter xx,$(join $1,$2)))
+
+# ----------------------------------------------------------------------------
+# Function: max, min
+# Arguments: 1: An integer
+# 2: Another integer
+# Returns: Returns the maximum or minimum of its integer arguments
+# ----------------------------------------------------------------------------
+max = $(__gmsl_tr2)$(call __gmsl_int_wrap,int_max,$1,$2)
+min = $(__gmsl_tr2)$(call __gmsl_int_wrap,int_min,$1,$2)
+
+# ----------------------------------------------------------------------------
+# Function: int_gt, int_gte, int_lt, int_lte, int_eq, int_ne
+# Arguments: Two x's representation numbers to be compared
+# Returns: $(true) or $(false)
+#
+# int_gt First argument greater than second argument
+# int_gte First argument greater than or equal to second argument
+# int_lt First argument less than second argument
+# int_lte First argument less than or equal to second argument
+# int_eq First argument is numerically equal to the second argument
+# int_ne First argument is not numerically equal to the second argument
+# ----------------------------------------------------------------------------
+int_gt = $(__gmsl_tr2)$(call __gmsl_make_bool, \
+ $(filter-out $(words $2), \
+ $(words $(call int_max,$1,$2))))
+int_gte = $(__gmsl_tr2)$(call __gmsl_make_bool, \
+ $(call int_gt,$1,$2)$(call int_eq,$1,$2))
+int_lt = $(__gmsl_tr2)$(call __gmsl_make_bool, \
+ $(filter-out $(words $1), \
+ $(words $(call int_max,$1,$2))))
+int_lte = $(__gmsl_tr2)$(call __gmsl_make_bool, \
+ $(call int_lt,$1,$2)$(call int_eq,$1,$2))
+int_eq = $(__gmsl_tr2)$(call __gmsl_make_bool, \
+ $(filter $(words $1),$(words $2)))
+int_ne = $(__gmsl_tr2)$(call __gmsl_make_bool, \
+ $(filter-out $(words $1),$(words $2)))
+
+# ----------------------------------------------------------------------------
+# Function: gt, gte, lt, lte, eq, ne
+# Arguments: Two integers to be compared
+# Returns: $(true) or $(false)
+#
+# gt First argument greater than second argument
+# gte First argument greater than or equal to second argument
+# lt First argument less than second argument
+# lte First argument less than or equal to second argument
+# eq First argument is numerically equal to the second argument
+# ne First argument is not numerically equal to the second argument
+# ----------------------------------------------------------------------------
+gt = $(__gmsl_tr2)$(call __gmsl_int_wrap2,int_gt,$1,$2)
+gte = $(__gmsl_tr2)$(call __gmsl_int_wrap2,int_gte,$1,$2)
+lt = $(__gmsl_tr2)$(call __gmsl_int_wrap2,int_lt,$1,$2)
+lte = $(__gmsl_tr2)$(call __gmsl_int_wrap2,int_lte,$1,$2)
+eq = $(__gmsl_tr2)$(call __gmsl_int_wrap2,int_eq,$1,$2)
+ne = $(__gmsl_tr2)$(call __gmsl_int_wrap2,int_ne,$1,$2)
+
+# increment adds 1 to its argument, decrement subtracts 1. Note that
+# decrement does not range check and hence will not underflow, but
+# will incorrectly say that 0 - 1 = 0
+
+# ----------------------------------------------------------------------------
+# Function: int_inc
+# Arguments: 1: A number in x's representation
+# Returns: The number incremented by 1 in x's representation
+# ----------------------------------------------------------------------------
+int_inc = $(strip $(__gmsl_tr1)$1 x)
+
+# ----------------------------------------------------------------------------
+# Function: inc
+# Arguments: 1: An integer
+# Returns: The argument incremented by 1
+# ----------------------------------------------------------------------------
+inc = $(__gmsl_tr1)$(call __gmsl_int_wrap1,int_inc,$1)
+
+# ----------------------------------------------------------------------------
+# Function: int_dec
+# Arguments: 1: A number in x's representation
+# Returns: The number decremented by 1 in x's representation
+# ----------------------------------------------------------------------------
+int_dec = $(__gmsl_tr1)$(strip $(if $(call sne,0,$(words $1)), \
+ $(wordlist 2,$(words $1),$1), \
+ $(call __gmsl_warning,Decrement underflow)))
+
+# ----------------------------------------------------------------------------
+# Function: dec
+# Arguments: 1: An integer
+# Returns: The argument decremented by 1
+# ----------------------------------------------------------------------------
+dec = $(__gmsl_tr1)$(call __gmsl_int_wrap1,int_dec,$1)
+
+# double doubles its argument, and halve halves it
+
+# ----------------------------------------------------------------------------
+# Function: int_double
+# Arguments: 1: A number in x's representation
+# Returns: The number doubled (i.e. * 2) and returned in x's representation
+# ----------------------------------------------------------------------------
+int_double = $(strip $(__gmsl_tr1)$1 $1)
+
+# ----------------------------------------------------------------------------
+# Function: double
+# Arguments: 1: An integer
+# Returns: The integer times 2
+# ----------------------------------------------------------------------------
+double = $(__gmsl_tr1)$(call __gmsl_int_wrap1,int_double,$1)
+
+# ----------------------------------------------------------------------------
+# Function: int_halve
+# Arguments: 1: A number in x's representation
+# Returns: The number halved (i.e. / 2) and returned in x's representation
+# ----------------------------------------------------------------------------
+int_halve = $(__gmsl_tr1)$(strip $(subst xx,x,$(filter-out xy x y, \
+ $(join $1,$(foreach a,$1,y x)))))
+
+# ----------------------------------------------------------------------------
+# Function: halve
+# Arguments: 1: An integer
+# Returns: The integer divided by 2
+# ----------------------------------------------------------------------------
+halve = $(__gmsl_tr1)$(call __gmsl_int_wrap1,int_halve,$1)
+
+ifdef __gmsl_have_eval
+# ###########################################################################
+# ASSOCIATIVE ARRAYS
+# ###########################################################################
+
+# ----------------------------------------------------------------------------
+# Function: set
+# Arguments: 1: Name of associative array
+# 2: The key value to associate
+# 3: The value associated with the key
+# Returns: None
+# ----------------------------------------------------------------------------
+set = $(__gmsl_tr3)$(eval __gmsl_aa_$1_$2 = $3)
+
+# ----------------------------------------------------------------------------
+# Function: get
+# Arguments: 1: Name of associative array
+# 2: The key to retrieve
+# Returns: The value stored in the array for that key
+# ----------------------------------------------------------------------------
+get = $(strip $(__gmsl_tr2)$(if $(filter-out undefined,$(origin __gmsl_aa_$1_$2)), \
+ $(__gmsl_aa_$1_$2)))
+
+# ----------------------------------------------------------------------------
+# Function: keys
+# Arguments: 1: Name of associative array
+# Returns: Returns a list of all defined keys in the array
+# ----------------------------------------------------------------------------
+keys = $(__gmsl_tr1)$(sort $(patsubst __gmsl_aa_$1_%,%, \
+ $(filter __gmsl_aa_$1_%,$(.VARIABLES))))
+
+# ----------------------------------------------------------------------------
+# Function: defined
+# Arguments: 1: Name of associative array
+# 2: The key to test
+# Returns: Returns true if the key is defined (i.e. not empty)
+# ----------------------------------------------------------------------------
+defined = $(__gmsl_tr2)$(call sne,$(call get,$1,$2),)
+
+endif # __gmsl_have_eval
+
+ifdef __gmsl_have_eval
+# ###########################################################################
+# NAMED STACKS
+# ###########################################################################
+
+# ----------------------------------------------------------------------------
+# Function: push
+# Arguments: 1: Name of stack
+# 2: Value to push onto the top of the stack (must not contain
+# a space)
+# Returns: None
+# ----------------------------------------------------------------------------
+push = $(__gmsl_tr2)$(eval __gmsl_stack_$1 := $2 $(if $(filter-out undefined,\
+ $(origin __gmsl_stack_$1)),$(__gmsl_stack_$1)))
+
+# ----------------------------------------------------------------------------
+# Function: pop
+# Arguments: 1: Name of stack
+# Returns: Top element from the stack after removing it
+# ----------------------------------------------------------------------------
+pop = $(__gmsl_tr1)$(strip $(if $(filter-out undefined,$(origin __gmsl_stack_$1)), \
+ $(call first,$(__gmsl_stack_$1)) \
+ $(eval __gmsl_stack_$1 := $(call rest,$(__gmsl_stack_$1)))))
+
+# ----------------------------------------------------------------------------
+# Function: peek
+# Arguments: 1: Name of stack
+# Returns: Top element from the stack without removing it
+# ----------------------------------------------------------------------------
+peek = $(__gmsl_tr1)$(call first,$(__gmsl_stack_$1))
+
+# ----------------------------------------------------------------------------
+# Function: depth
+# Arguments: 1: Name of stack
+# Returns: Number of items on the stack
+# ----------------------------------------------------------------------------
+depth = $(__gmsl_tr1)$(words $(__gmsl_stack_$1))
+
+endif # __gmsl_have_eval
+
+# ###########################################################################
+# DEBUGGING FACILITIES
+# ###########################################################################
+
+# ----------------------------------------------------------------------------
+# Target: gmsl-print-%
+# Arguments: The % should be replaced by the name of a variable that you
+# wish to print out.
+# Action: Echos the name of the variable that matches the % and its value.
+# For example, 'make gmsl-print-SHELL' will output the value of
+# the SHELL variable
+# ----------------------------------------------------------------------------
+gmsl-print-%: ; @echo $* = $($*)
+
+# ----------------------------------------------------------------------------
+# Function: assert
+# Arguments: 1: A boolean that must be true or the assertion will fail
+# 2: The message to print with the assertion
+# Returns: None
+# ----------------------------------------------------------------------------
+assert = $(if $1,,$(call __gmsl_error,Assertion failure: $2))
+
+# ----------------------------------------------------------------------------
+# Function: assert_exists
+# Arguments: 1: Name of file that must exist, if it is missing an assertion
+# will be generated
+# Returns: None
+# ----------------------------------------------------------------------------
+assert_exists = $(call assert,$(wildcard $1),file '$1' missing)