**String comparisons - compare match first last wordend**


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There are 6 string subcommands that do pattern and string matching.  These are relatively fast operations, certainly faster than regular expressions, albeit less powerful. 
`string compare`
`string1`
`string2`
</dt>

   '''''':    Compares `string1` to `string2` and returns:  <ul> <li>-1 ..... If `string1` is less than `string2` <li> 0 ........ If `string1` is equal to `string2` <li> 1 ........ If `string1` is greater than `string2` </ul>  These comparisons are done alphabetically, not numerically - in other words "a" is less than "b", and "10" is less than "2". 

`string first`
`string1`
`string2`
</dt>
   '''''':    Returns the index of the character in `string1` that starts the first match to `string2`, or -1 if there is no match. 


`string last`
`string1`
`string2`
</dt>
   '''''':    Returns the index of the character in `string1` that starts the last match to `string2`, or -1 if there is no match. 

`string wordend`
`string`
`index`
</dt>
   '''''':    Returns the index of the character just after the last one in the word which contains the `index`'th character of `string`.  A word is any contiguous set of letters, numbers or underscore characters, or a single other character. 
`string wordstart`
`string`
`index`
</dt>
   '''''':    Returns the index of the first character in the word that contains the `index`'th character of `string`. A word is any contiguous set of letters, numbers or underscore characters, or a single other character. 
`string match`
`pattern`
`string`
</dt>
   '''''':    Returns 1 if the `pattern` matches `string`.  The `pattern` is a <a href="Tcl16a.html">glob</a> style pattern. 


----

***Example***

======
set fullpath "/usr/home/clif/TCL_STUFF/TclTutor/Lsn.17"
set relativepath "CVS/Entries"
set directorypath "/usr/bin/"

set paths [list $fullpath $relativepath $directorypath]

foreach path $paths  {
    set first [string first "/" $path]
    set last [string last "/" $path]

    # Report whether path is absolute or relative

    if {$first != 0} {
        puts "$path is a relative path"
    } else {
        puts "$path is an absolute path"
    }

    # If "/" is not the last character in $path, report the last word.
    # else, remove the last "/", and find the next to last "/", and
    #   report the last word.

    incr last
    if {$last != [string length $path]} {
        set name [string range $path $last end]
        puts "The file referenced in $path is $name"
    } else {
        incr last -2;
        set tmp [string range $path 0 $last]
        set last [string last "/" $tmp]
        incr last;
        set name [string range $tmp $last end]
        puts "The final directory in $path is $name"
    }

    # CVS is a directory created by the CVS source code control system.
    #

    if {[string match "*CVS*" $path]} {
        puts "$path is part of the source code control tree"
    }

    # Compare to "a" to determine whether the first char is upper or lower case
    set comparison [string  compare $name "a"]
    if {$comparison >= 0} {
        puts "$name starts with a lowercase letter\n"
    } else {
        puts "$name starts with an uppercase letter\n"
    }
}
======



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