array tcl

Overview

Manipulate array variables

Syntax

array option arrayName ?arg arg ...?

Description

This command performs one of several operations on the variable given by arrayName. ArrayName must be the name of an existing array variable. The option argument determines what action is carried out by the command. The legal options (which may be abbreviated) are:

array anymore arrayName searchId

Returns 1 if there are any more elements left to be processed in an array search, 0 if all elements have already been returned. SearchId indicates the search on arrayName to check, and must have been the return value from a previous invocation of array startsearch. This option is particularly useful if an array has an element with an empty name, since the return value from array nextelement won't indicate whether the search has been completed.

array donesearch arrayName searchId.

This command terminates an array search and destroys all the state associated with that search. SearchId indicates the search on arrayName to destroy, and must have been the return value from a previous invocation of array startsearch. Returns an empty string.

array names arrayName

Returns a list containing the names of all of the elements in the array. If there are no elements in the array then an empty string is returned.

array nextelement arrayName searchId

Returns the name of the next element in arrayName, or an empty string if all elements of arrayName have already been returned in this search. The searchId argument identifies the search, and must have been the return value of an array startsearch command. Warning: if elements are added to or deleted from the array, then all searches are automatically terminated just as if array donesearch had been invoked; this will cause array nextelement operations to fail for those searches.

array size arrayName

Returns a decimal string giving the number of elements in the array.

array startsearch arrayName

This command initializes an element-by-element search through the array given by arrayName, such that invocations of the array nextelement command will return the names of the individual elements in the array. When the search has been completed, the array donesearch command should be invoked. The return value is a search identifier that must be used in array nextelement and array donesearch commands; it allows multiple searches to be underway simultaneously for the same array.

Keywords

array, element names, search