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lreplace(n)		     Tcl Built-In Commands		   lreplace(n)

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NAME
       lreplace	- Replace elements in a	list with new elements

SYNOPSIS
       lreplace	list first last	?element element ...?
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DESCRIPTION
       lreplace	 returns  a new	list formed by replacing zero or more elements
       of list with the	element	arguments.  first and last  are	 index	values
       specifying  the	first  and last	elements of the	range to replace.  The
       index values first and last are interpreted the same  as	 index	values
       for  the	 command  string index,	supporting simple index	arithmetic and
       indices relative	to the end of the list.	 0 refers to the first element
       of the list, and	end refers to the last element of the list.

       If either first or last is less than zero, it is	considered to refer to
       before the first	element	of the list. This allows lreplace  to  prepend
       elements	to list.  If either first or last indicates a position greater |
       than the	index of the last element of the list, it is treated as	if  it |
       is  an index one	greater	than the last element. This allows lreplace to |
       append elements to list.

       If last is less than first, then	any specified  elements	 will  be  in-
       serted into the list before the element specified by first with no ele-
       ments being deleted.

       The element arguments specify zero or more new elements to be added  to
       the  list  in  place of those that were deleted.	 Each element argument
       will become a separate element of the list.  If	no  element  arguments
       are  specified,	then  the  elements  between first and last are	simply
       deleted.

EXAMPLES
       Replacing an element of a list with another:

	      %	lreplace {a b c	d e} 1 1 foo
	      a	foo c d	e

       Replacing two elements of a list	with three:

	      %	lreplace {a b c	d e} 1 2 three more elements
	      a	three more elements d e

       Deleting	the last element from a	list in	a variable:

	      %	set var	{a b c d e}
	      a	b c d e
	      %	set var	[lreplace $var end end]
	      a	b c d

       A procedure to delete a given element from a list:

	      proc lremove {listVariable value}	{
		  upvar	1 $listVariable	var
		  set idx [lsearch -exact $var $value]
		  set var [lreplace $var $idx $idx]
	      }

       Appending elements to the list;	note  that  end+2  will	 initially  be |
       treated	as  if	it is 6	here, but both that and	12345 are greater than |
       the index of the	final item so they behave identically:		       |

	      %	set var	{a b c d e}					       |
	      a	b c d e							       |
	      %	set var	[lreplace $var 12345 end+2 f g h i]		       |
	      a	b c d e	f g h i						       |

SEE ALSO
       list(n),	lappend(n),  lindex(n),	 linsert(n),  llength(n),  lsearch(n),
       lset(n),	lrange(n), lsort(n), string(n)

KEYWORDS
       element,	list, replace

Tcl				      7.4			   lreplace(n)

NAME | SYNOPSIS | DESCRIPTION | EXAMPLES | SEE ALSO | KEYWORDS

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