osx man page for lindex

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

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NAME
       lindex - Retrieve an element from a list

SYNOPSIS
       lindex list ?index...?
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DESCRIPTION
       The  lindex  command  accepts  a  parameter,  list, which it treats as a Tcl list. It also accepts zero or more indices into the list.  The
       indices may be presented either consecutively on the command line, or grouped in a Tcl list and presented as a single argument.

       If no indices are presented, the command takes the form:
	      lindex list
       or
	      lindex list {}
       In this case, the return value of lindex is simply the value of the list parameter.

       When presented with a single index, the lindex command treats list as a Tcl list and returns the index'th element from it (0 refers to  the
       first  element of the list).  In extracting the element, lindex observes the same rules concerning braces and quotes and backslashes as the
       Tcl command interpreter; however, variable substitution and command substitution do not occur.  If index is negative  or  greater  than	or
       equal  to  the number of elements in value, then an empty string is returned.  The interpretation of each simple index value is the same as |
       for the command string index, supporting simple index arithmetic and indices relative to the end of the list.

       If additional index arguments are supplied, then each argument is used in turn to select an element from the previous  indexing	operation,
       allowing the script to select elements from sublists.  The command,
	      lindex $a 1 2 3
       or
	      lindex $a {1 2 3}
       is synonymous with
	      lindex [lindex [lindex $a 1] 2] 3

EXAMPLES
	      lindex {a b c}
		    -> a b c
	      lindex {a b c} {}
		    -> a b c
	      lindex {a b c} 0
		    -> a
	      lindex {a b c} 2
		    -> c
	      lindex {a b c} end
		    -> c
	      lindex {a b c} end-1
		    -> b
	      lindex {{a b c} {d e f} {g h i}} 2 1
		    -> h
	      lindex {{a b c} {d e f} {g h i}} {2 1}
		    -> h
	      lindex {{{a b} {c d}} {{e f} {g h}}} 1 1 0
		    -> g
	      lindex {{{a b} {c d}} {{e f} {g h}}} {1 1 0}
		    -> g

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

KEYWORDS
       element, index, list

Tcl									8.4								 lindex(n)