Command introduced in Tcl 8.6 for easier management of the prefix-matching of strings.
http://www.tcl.tk/man/tcl8.6/TclCmd/prefix.htm

tcl::prefix subcommand …

Currently supports three subcommands.

tcl::prefix all table string

This returns all values from the list, table, that start with string. (This answers the question “what values in the table start with a prefix?”)

tcl::prefix longest table string

Returns the longest prefix of the subset of values in the list, table, such that the values all begin with string. (This answers the question “what can I extend my current prefix to, while not changing the set of words which I've got a prefix of?” which is useful for tab-completion.)

tcl::prefix match options… table string

Returns the unique entry from the list, table, that string is a prefix of, or generates an error message.

See Also edit

• Forward-compatible tcl::prefix

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