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struct::stack(3tcl) Tcl Data Structures struct::stack(3tcl) 





NAME


struct::stack - Create and manipulate stack objects






SYNOPSIS


package require Tcl 8.4


package require struct::stack ?1.5.3?


stackName option ?arg arg ...?


stackName clear


stackName destroy


stackName get


stackName getr


stackName peek ?count?


stackName peekr ?count?


stackName trim ?newsize?


stackName trim* ?newsize?


stackName pop ?count?


stackName push item ?item...?


stackName size










DESCRIPTION


The ::struct namespace contains a commands for processing
    finite stacks.


It exports a single command, ::struct::stack. All
    functionality provided here can be reached through a subcommand of this
    command.


Note: As of version 1.3.3 of this package a critcl based C
    implementation is available. This implementation however requires Tcl 8.4 to
    run.


The ::struct::stack command creates a new stack object with
    an associated global Tcl command whose name is stackName. This
    command may be used to invoke various operations on the stack. It has the
    following general form:



  

  
Option and the args determine the exact behavior of the
      command. The following commands are possible for stack objects:

  

  
Remove all items from the stack.

  

  
Destroy the stack, including its storage space and associated
    command.

  

  
Returns the whole contents of the stack as a list, without removing them
      from the stack.

  

  
A variant of get, which returns the contents in reversed
    order.

  

  
Return the top count items of the stack, without removing them from
      the stack. If count is not specified, it defaults to 1. If
      count is 1, the result is a simple string; otherwise, it is a list.
      If specified, count must be greater than or equal to 1. If there
      are not enoughs items on the stack to fulfull the request, this command
      will throw an error.

  

  
A variant of peek, which returns the items in reversed order.

  

  
Shrinks the stack to contain at most newsize elements and returns a
      list containing the elements which were removed. Nothing is done if the
      stack is already at the specified size, or smaller. In that case the
      result is the empty list.

  

  
A variant of trim which performs the shrinking, but does not return
      the removed elements.

  

  
Return the top count items of the stack, and remove them from the
      stack. If count is not specified, it defaults to 1. If count
      is 1, the result is a simple string; otherwise, it is a list. If
      specified, count must be greater than or equal to 1. If there are
      not enoughs items on the stack to fulfull the request, this command will
      throw an error.

  

  
Push the item or items specified onto the stack. If more than one
      item is given, they will be pushed in the order they are
    listed.

  

  
Return the number of items on the stack.








BUGS, IDEAS, FEEDBACK


This document, and the package it describes, will undoubtedly
    contain bugs and other problems. Please report such in the category
    struct :: stack of the Tcllib Trackers
    [http://core.tcl.tk/tcllib/reportlist]. Please also report any ideas for
    enhancements you may have for either package and/or documentation.


When proposing code changes, please provide unified diffs,
    i.e the output of diff -u.


Note further that attachments are strongly preferred over
    inlined patches. Attachments can be made by going to the Edit form of
    the ticket immediately after its creation, and then using the left-most
    button in the secondary navigation bar.






KEYWORDS


graph, matrix, queue, tree






CATEGORY


Data structures







  

    1.5.3
    tcllib