1struct::stack(n) Tcl Data Structures struct::stack(n)
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8 struct::stack - Create and manipulate stack objects
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11 package require Tcl 8.4
12 package require struct::stack ?1.5.3?
14 stackName option ?arg arg ...?
16 stackName clear
18 stackName destroy
20 stackName get
22 stackName getr
24 stackName peek ?count?
26 stackName peekr ?count?
28 stackName trim ?newsize?
30 stackName trim* ?newsize?
32 stackName pop ?count?
34 stackName push item ?item...?
36 stackName size
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40
42 The ::struct namespace contains a commands for processing finite
43 stacks.
44 It exports a single command, ::struct::stack. All functionality pro‐
46 vided here can be reached through a subcommand of this command.
47 Note: As of version 1.3.3 of this package a critcl based C implementa‐
49 tion is available. This implementation however requires Tcl 8.4 to run.
50 The ::struct::stack command creates a new stack object with an associ‐
52 ated global Tcl command whose name is stackName. This command may be
53 used to invoke various operations on the stack. It has the following
54 general form:
55 stackName option ?arg arg ...?
57 Option and the args determine the exact behavior of the command.
58 The following commands are possible for stack objects:
59 stackName clear
61 Remove all items from the stack.
62 stackName destroy
64 Destroy the stack, including its storage space and associated
65 command.
66 stackName get
68 Returns the whole contents of the stack as a list, without re‐
69 moving them from the stack.
70 stackName getr
72 A variant of get, which returns the contents in reversed order.
73 stackName peek ?count?
75 Return the top count items of the stack, without removing them
76 from the stack. If count is not specified, it defaults to 1.
77 If count is 1, the result is a simple string; otherwise, it is a
78 list. If specified, count must be greater than or equal to 1.
79 If there are not enoughs items on the stack to fulfull the re‐
80 quest, this command will throw an error.
81 stackName peekr ?count?
83 A variant of peek, which returns the items in reversed order.
84 stackName trim ?newsize?
86 Shrinks the stack to contain at most newsize elements and re‐
87 turns a list containing the elements which were removed. Nothing
88 is done if the stack is already at the specified size, or
89 smaller. In that case the result is the empty list.
90 stackName trim* ?newsize?
92 A variant of trim which performs the shrinking, but does not re‐
93 turn the removed elements.
94 stackName pop ?count?
96 Return the top count items of the stack, and remove them from
97 the stack. If count is not specified, it defaults to 1. If
98 count is 1, the result is a simple string; otherwise, it is a
99 list. If specified, count must be greater than or equal to 1.
100 If there are not enoughs items on the stack to fulfull the re‐
101 quest, this command will throw an error.
102 stackName push item ?item...?
104 Push the item or items specified onto the stack. If more than
105 one item is given, they will be pushed in the order they are
106 listed.
107 stackName size
109 Return the number of items on the stack.
110
112 This document, and the package it describes, will undoubtedly contain
113 bugs and other problems. Please report such in the category struct ::
114 stack of the Tcllib Trackers [http://core.tcl.tk/tcllib/reportlist].
115 Please also report any ideas for enhancements you may have for either
116 package and/or documentation.
117 When proposing code changes, please provide unified diffs, i.e the out‐
119 put of diff -u.
120 Note further that attachments are strongly preferred over inlined
122 patches. Attachments can be made by going to the Edit form of the
123 ticket immediately after its creation, and then using the left-most
124 button in the secondary navigation bar.
125
127 graph, matrix, queue, tree
128
130 Data structures
131tcllib 1.5.3 struct::stack(n)