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OpenDarwin 7.2.1 - man page for lindex (opendarwin section n)

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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  consecu- |
       tively 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.  If  index	has  the  value  end,  it
       refers  to the last element in the list, and end-integer refers to the last element in the
       list minus the specified integer offset.

       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)

KEYWORDS
       element, index, list

Tcl					       8.4					lindex(n)
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