lrange

Name

lrange — Return one or more adjacent elements from a list

Synopsis

lrange list first last

Description

List must be a valid Tcl list. This command will return a new list consisting of elements first through last, inclusive. 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. If first is less than zero, it is treated as if it were zero. If last is greater than or equal to the number of elements in the list, then it is treated as if it were end. If first is greater than last then an empty string is returned.

Note that “lrange list first first” does not always produce the same result as “lindex list first” (although it often does for simple fields that are not enclosed in braces); it does, however, produce exactly the same results as “list [lindex list first]”

Examples

Selecting the first two elements:

% lrange {a b c d e} 0 1
a b

Selecting the last three elements:

% lrange {a b c d e} end-2 end
c d e

Selecting everything except the first and last element:

% lrange {a b c d e} 1 end-1
b c d

Selecting a single element with lrange is not the same as doing so with lindex:

% set var {some {elements to} select}
some {elements to} select
% lindex $var 1
elements to
% lrange $var 1 1
{elements to}

See also

list, lappend, lassign, ledit, lindex, linsert, llength, lmap, lpop, lremove, lrepeat, lreplace, lreverse, lsearch, lseq, lset, lsort, string