Summary

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	File:     sort.icn

	Subject:  Procedures for sorting

	Authors:  Bob Alexander, Richard L. Goerwitz, and Ralph E. Griswold

	Date:     September 10, 1998

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   This file is in the public domain.

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	isort(x, p)
		customized sort in which procedure p is used for
		comparison.

	sortff(L, fields[])
		like sortf(), except takes an unlimited number of field
		arguments.

	sortgen(T, m)
		generates sorted output in a manner specified by m:

			"k+"	sort by key in ascending order
			"k-"	sort by key in descending order
			"v+"	sort by value in ascending order
			"v-"	sort by value in descending order

	sortt(T, i)
		like sort(T, i) but produces a list of two-element records
		instead of a list of two-element lists.

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  Customizable sort procedure for inclusion in Icon programs.

       isort(x,keyproc,y)

  Argument x can be any Icon data type that is divisible into elements
  by the unary element generation (!) operator.  The result is a list
  of the objects in sorted order.

  The default is to sort elements in their natural, Icon-defined order.
  However, an optional parameter (keyproc) allows a sort key to be
  derived from each element, rather than the default of using the
  element itself as the key.  Keyproc can be a procedure provided by
  the caller, in which case the first argument to the key procedure is
  the item for which the key is to be computed, and the second argument
  is isort's argument y, passed unchanged.  The keyproc must produce
  the extracted key.  Alternatively, the keyproc argument can be an
  integer, in which case it specifies a subscript to be applied to each
  item to produce a key.  Keyproc will be called once for each element
  of structure x.

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This file is part of the (main) package.

isort(x, keyproc, y)

sortff(L, fields)

: sort on multiple fields

sortff_1(L, fields, k, uniqueObject)

sortgen(T, m)

: generate by different sorting orders

sortt(T, i)

: sort to produce list of records

element(key, value)