Word Designators (Debugging with GDB)

#### 34.1.2 Word Designators ¶

Word designators are used to select desired words from the event. A ‘`:`’ separates the event specification from the word designator. It may be omitted if the word designator begins with a ‘`^`’, ‘`$`’, ‘`*`’, ‘`-`’, or ‘`%`’. Words are numbered from the beginning of the line, with the first word being denoted by 0 (zero). Words are inserted into the current line separated by single spaces.

For example,

`!!`

  designates the preceding command. When you type this, the preceding command is repeated in toto.

`!!:$`

  designates the last argument of the preceding command. This may be shortened to `!$`.

`!fi:2`

  designates the second argument of the most recent command starting with the letters `fi`.

Here are the word designators:

`0 (zero)`

  The `0`th word. For many applications, this is the command word.

`n`

  The nth word.

`^`

  The first argument; that is, word 1.

`$`

  The last argument.

`%`

  The first word matched by the most recent ‘`?string?`’ search, if the search string begins with a character that is part of a word.

`x-y`

  A range of words; ‘`-y`’ abbreviates ‘`0-y`’.

`*`

  All of the words, except the `0`th. This is a synonym for ‘`1-$`’. It is not an error to use ‘`*`’ if there is just one word in the event; the empty string is returned in that case.

`x*`

  Abbreviates ‘`x-$`’

`x-`

  Abbreviates ‘`x-$`’ like ‘`x*`’, but omits the last word. If ‘`x`’ is missing, it defaults to 0.

If a word designator is supplied without an event specification, the previous command is used as the event.