**Modifying Strings - tolower, toupper, trim, format**


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These are the commands which modify a string.  Note that none of these modify the string in place.  In all cases a new string is returned. 

`string`
`tolower`
`string`
</dt>
   '''''':    Returns `string` with all the letters converted from upper to lower case. 

`string`
`toupper`
`string`
</dt>
   '''''':    Returns `string` with all the letters converted from lower to upper case. 

`string`
`trim`
`string`
`?trimChars?`
   '''''':    Returns `string` with all occurrences of `trimChars` removed from both ends. By default `trimChars` are whitespace (spaces, tabs, newlines).  Note that the characters are not treated as a "block" of characters - in other words, `string trim "davidw" dw` would return the string `avi` and not `davi`. 

`string`
`trimleft`
`string`
`?trimChars?`
</dt>
   '''''':    Returns `string` with all occurrences of `trimChars` removed from the left. By default `trimChars` are whitespace (spaces, tabs, newlines) 

`string`
`trimright`
`string`
`?trimChars?`
</dt>
   '''''':    Returns `string` with all occurrences of `trimChars` removed from the right. By default `trimChars` are whitespace (spaces, tabs, newlines) 

`format`
`formatString`
`?arg1 arg2 ... argN?`
</dt>