    indexing
    	description: "[
    		Access to command-line arguments. This class
    		may be used as ancestor by classes needing its facilities.
    	]"
    	legal: "See notice at end of class."
    	status: "See notice at end of class."
    	date: "$Date: 2006-07-19 17:53:57 -0700 (Wed, 19 Jul 2006) $"
    	revision: "$Revision: 61495 $"

    class interface
    	ARGUMENTS

    create
    	default_create
    			-- Process instances of classes with no creation clause.
    			-- (Default: do nothing.)
    			-- (from ANY)

    feature -- Access

    	argument (i: INTEGER_32): STRING_8
    			-- `i'-th argument of command that started system execution
    			-- (the command name if `i' = 0)
    		require
    			index_large_enough: i >= 0
    			index_small_enough: i <= argument_count

    	argument_array: ARRAY [STRING_8]
    			-- Array containing command name (position 0) and arguments
    		ensure
    			argument_array_not_void: Result /= Void

    	command_line: STRING_8
    			-- Total command line
    		ensure
    			Result.count >= command_name.count

    	command_name: STRING_8
    			-- Name of command that started system execution
    		ensure
    			definition: Result.is_equal (argument (0))

    	generating_type: STRING_8
    			-- Name of current object's generating type
    			-- (type of which it is a direct instance)
    			-- (from ANY)

    	generator: STRING_8
    			-- Name of current object's generating class
    			-- (base class of the type of which it is a direct instance)
    			-- (from ANY)

    feature -- Measurement

    	argument_count: INTEGER_32
    			-- Number of arguments given to command that started
    			-- system execution (command name does not count)
    		ensure
    			Result >= 0

    feature -- Comparison

    	frozen deep_equal (some: ANY; other: like arg #1): BOOLEAN
    			-- Are `some' and `other' either both void
    			-- or attached to isomorphic object structures?
    			-- (from ANY)
    		ensure -- from ANY
    			shallow_implies_deep: standard_equal (some, other) implies Result
    			both_or_none_void: (some = Void) implies (Result = (other = Void))
    			same_type: (Result and (some /= Void)) implies some.same_type (other)
    			symmetric: Result implies deep_equal (other, some)

    	frozen equal (some: ANY; other: like arg #1): BOOLEAN
    			-- Are `some' and `other' either both void or attached
    			-- to objects considered equal?
    			-- (from ANY)
    		ensure -- from ANY
    			definition: Result = (some = Void and other = Void) or else ((some /= Void and other /= Void) and then some.is_equal (other))

    	is_equal (other: like Current): BOOLEAN
    			-- Is `other' attached to an object considered
    			-- equal to current object?
    			-- (from ANY)
    		require -- from ANY
    			other_not_void: other /= Void
    		ensure -- from ANY
    			symmetric: Result implies other.is_equal (Current)
    			consistent: standard_is_equal (other) implies Result

    	frozen standard_equal (some: ANY; other: like arg #1): BOOLEAN
    			-- Are `some' and `other' either both void or attached to
    			-- field-by-field identical objects of the same type?
    			-- Always uses default object comparison criterion.
    			-- (from ANY)
    		ensure -- from ANY
    			definition: Result = (some = Void and other = Void) or else ((some /= Void and other /= Void) and then some.standard_is_equal (other))

    	frozen standard_is_equal (other: like Current): BOOLEAN
    			-- Is `other' attached to an object of the same type
    			-- as current object, and field-by-field identical to it?
    			-- (from ANY)
    		require -- from ANY
    			other_not_void: other /= Void
    		ensure -- from ANY
    			same_type: Result implies same_type (other)
    			symmetric: Result implies other.standard_is_equal (Current)

    feature -- Status report

    	coalesced_character_option_value (o: CHARACTER_8): STRING_8
    			-- The value, if any, specified for character option `o' on
    			-- the command line.
    			-- Defined as follows (where 'X' is the current 'option_sign' and
    			-- 'xx' is an arbitrary, possibly empty sequence of characters):
    			--   `val' if command line includes an argument of the form `Xxxoval'
    			--	   (this may be an empty string if argument is just `Xxxo').
    			--   Void otherwise.
    		require
    			o_non_null: o /= '%U'

    	coalesced_word_option_value (opt: STRING_8): STRING_8
    			-- The value, if any, specified for word option `opt' on the
    			-- command line.
    			-- Defined as follows (where X is the current Option_sign):
    			--   `val' if command line includes an argument of the form `Xoptval'
    			--	   (this may be an empty string if argument is just `Xopt').
    			--   Void otherwise.
    		require
    			opt_non_void: opt /= Void
    			opt_meaningful: not opt.is_empty

    	conforms_to (other: ANY): BOOLEAN
    			-- Does type of current object conform to type
    			-- of `other' (as per Eiffel: The Language, chapter 13)?
    			-- (from ANY)
    		require -- from ANY
    			other_not_void: other /= Void

    	index_of_beginning_with_word_option (opt: STRING_8): INTEGER_32
    			-- Does command line specify argument beginning with word
    			-- option `opt' and, if so, at what position?
    			-- If one of the arguments in list of space-separated arguments
    			-- is `Xoptxx', where `X' is the current Option_sign, 'xx'
    			-- is arbitrary, possibly empty sequence of characters,
    			-- then index of this argument in list;
    			-- else 0.
    		require
    			opt_non_void: opt /= Void
    			opt_meaningful: not opt.is_empty

    	index_of_character_option (o: CHARACTER_8): INTEGER_32
    			-- Does command line specify character option `o' and, if so,
    			-- at what position?
    			-- If one of the space-separated arguments is of the form `Xxxoyy',
    			-- where `X' is the current Option_sign, `xx' and `yy'
    			-- are arbitrary, possibly empty sequences of characters,
    			-- then index of this argument in list of arguments;
    			-- else 0.
    		require
    			o_non_null: o /= '%U'

    	index_of_word_option (opt: STRING_8): INTEGER_32
    			-- Does command line specify word option `opt' and, if so,
    			-- at what position?
    			-- If one of the arguments in list of space-separated arguments
    			-- is `Xopt', where `X' is the current Option_sign,
    			-- then index of this argument in list;
    			-- else 0.
    		require
    			opt_non_void: opt /= Void
    			opt_meaningful: not opt.is_empty

    	option_sign: CHARACTER_8_REF
    			-- The character used to signal options on the command line.
    			-- This can be '%U' if no sign is necesary for the argument
    			-- to be an option
    			-- Default is '-'

    	same_type (other: ANY): BOOLEAN
    			-- Is type of current object identical to type of `other'?
    			-- (from ANY)
    		require -- from ANY
    			other_not_void: other /= Void
    		ensure -- from ANY
    			definition: Result = (conforms_to (other) and other.conforms_to (Current))

    	separate_character_option_value (o: CHARACTER_8): STRING_8
    			-- The value, if any, specified after character option `o' on
    			-- the command line.
    			-- This is one of the following (where `X' is the current
    			-- Option_sign, `xx' and 'yy' are arbitrary, possibly empty
    			-- sequences of characters):
    			--   `val' if command line includes two consecutive arguments
    			--	   of the form `Xxxoyy' and `val' respectively.
    			--   Empty string if command line includes argument `Xxxoyy', which is
    			--	   either last argument or followed by argument starting with `X'.
    			--   Void if there is no argument of the form `Xxxoyy'.
    		require
    			o_non_null: o /= '%U'

    	separate_word_option_value (opt: STRING_8): STRING_8
    			-- The value, if any, specified after word option `opt' on the
    			-- command line.
    			-- This is one of the following (where `X' is the current Option_sign):
    			--   `val' if command line includes two consecutive arguments
    			--	   of the form `Xopt' and `val' respectively.
    			--   Empty string if command line includes argument `Xopt', which is
    			--	   either last argument or followed by argument starting with `X'.
    			--   Void if no `Xopt' argument.
    		require
    			opt_non_void: opt /= Void
    			opt_meaningful: not opt.is_empty

    feature -- Status setting

    	set_option_sign (c: CHARACTER_8)
    			-- Make `c' the option sign.
    			-- Use'%U' if no sign is necesary for the argument to
    			-- be an option

    feature -- Duplication

    	copy (other: like Current)
    			-- Update current object using fields of object attached
    			-- to `other', so as to yield equal objects.
    			-- (from ANY)
    		require -- from ANY
    			other_not_void: other /= Void
    			type_identity: same_type (other)
    		ensure -- from ANY
    			is_equal: is_equal (other)

    	frozen deep_copy (other: like Current)
    			-- Effect equivalent to that of:
    			--		copy (`other' . deep_twin)
    			-- (from ANY)
    		require -- from ANY
    			other_not_void: other /= Void
    		ensure -- from ANY
    			deep_equal: deep_equal (Current, other)

    	frozen deep_twin: like Current
    			-- New object structure recursively duplicated from Current.
    			-- (from ANY)
    		ensure -- from ANY
    			deep_equal: deep_equal (Current, Result)

    	frozen standard_copy (other: like Current)
    			-- Copy every field of `other' onto corresponding field
    			-- of current object.
    			-- (from ANY)
    		require -- from ANY
    			other_not_void: other /= Void
    			type_identity: same_type (other)
    		ensure -- from ANY
    			is_standard_equal: standard_is_equal (other)

    	frozen standard_twin: like Current
    			-- New object field-by-field identical to `other'.
    			-- Always uses default copying semantics.
    			-- (from ANY)
    		ensure -- from ANY
    			standard_twin_not_void: Result /= Void
    			equal: standard_equal (Result, Current)

    	frozen twin: like Current
    			-- New object equal to `Current'
    			-- twin calls copy; to change copying/twining semantics, redefine copy.
    			-- (from ANY)
    		ensure -- from ANY
    			twin_not_void: Result /= Void
    			is_equal: Result.is_equal (Current)

    feature -- Basic operations

    	frozen default: like Current
    			-- Default value of object's type
    			-- (from ANY)

    	frozen default_pointer: POINTER
    			-- Default value of type `POINTER'
    			-- (Avoid the need to write `p'.default for
    			-- some `p' of type `POINTER'.)
    			-- (from ANY)

    	default_rescue
    			-- Process exception for routines with no Rescue clause.
    			-- (Default: do nothing.)
    			-- (from ANY)

    	frozen do_nothing
    			-- Execute a null action.
    			-- (from ANY)

    feature -- Output

    	io: STD_FILES
    			-- Handle to standard file setup
    			-- (from ANY)

    	out: STRING_8
    			-- New string containing terse printable representation
    			-- of current object
    			-- Was declared in ANY as synonym of tagged_out.
    			-- (from ANY)

    	print (some: ANY)
    			-- Write terse external representation of `some'
    			-- on standard output.
    			-- (from ANY)

    	frozen tagged_out: STRING_8
    			-- New string containing terse printable representation
    			-- of current object
    			-- Was declared in ANY as synonym of out.
    			-- (from ANY)

    feature -- Platform

    	operating_environment: OPERATING_ENVIRONMENT
    			-- Objects available from the operating system
    			-- (from ANY)

    invariant
    		-- from ANY
    	reflexive_equality: standard_is_equal (Current)
    	reflexive_conformance: conforms_to (Current)

    indexing
    	library: "EiffelBase: Library of reusable components for Eiffel."
    	copyright: "Copyright (c) 1984-2006, Eiffel Software and others"
    	license: "Eiffel Forum License v2 (see http://www.eiffel.com/licensing/forum.txt)"
    	source: "[
    		Eiffel Software
    		356 Storke Road, Goleta, CA 93117 USA
    		Telephone 805-685-1006, Fax 805-685-6869
    		Website http://www.eiffel.com
    		Customer support http://support.eiffel.com
    	]"

    end -- class ARGUMENTS