Can you grab or delete between parentheses in vi/vim?

Question

What about dib or di(.

It will delete the inner (...) block where the cursor is.

I love text-object motions and selections!

Various Motions: %

The % command jumps to the match of the item under the cursor. Position the cursor on the opening (or closing) paren and use y% for yanking or d% for deleting everything from the cursor to the matching paren.

This works because % is a "motion command", so it can be used anywhere vim expects such a command. From :help y:

["x]y{motion}       Yank {motion} text [into register x].  When no
                    characters are to be yanked (e.g., "y0" in column 1),
                    this is an error when 'cpoptions' includes the 'E'
                    flag.

By default, "item" includes brackets, braces, parens, C-style comments and various precompiler statements (#ifdef, etc.).

There is a plugin for "extended % matching" that you can find on the Vim homepage.

You can read the documentation on % and related motion commands by entering :help various-motions in command mode.

object-select

There is another set of motion commands that you can use in Visual mode to select various text objects.

To solve your specific problem you would do the following:

printf("%3.0f\t%6.1f\n", fahr, ((5.0/9.0) * (fahr-32)));
                                   ^

Let's say your cursor is positioned at ^. Enter the following sequence to select the part you are looking for:

v2a)

First v enters Visual mode, then you specify that you want to go 2 levels of parens up. Finally the a) selects "a block". After that you can use d or x to delete, etc.

If you don't want to include the outer parens, you can use "inner block" instead:

v2i)

See :help object-select for the complete list of related commands.

To delete all that is inside a pair of parentheses, you can always issue di( and its derivatives.

Note :

As @porglezomb suggested in his comment, you can use a ("along with") instead of i ("inside") to include the parentheses. So, using da( deletes everything inside ( and ) including ( and ).

Deleting text inside the immediate outer pair of parentheses :

So, for this line of code

printf("%3.0f\t%6.1f\n", fahr, ((5.0/9.0) * (fahr-32)));
                                ^       ^
                                |       |
                                 \_______\___---> Cursor range

assuming that your cursor is inside the above mentioned cursor range, you can issue the following commands :

di(   --> Deletes '5.0/9.0'
ci(   --> Substitutes '5.0/9.0'
yi(   --> Yanks '5.0/9.0'

Deleting text inside the n-th outer pair of parentheses :

To grab everything inside the n-th outer pair of parentheses, just add n before the above command. So, with the same cursor position as above,

2di(   --> Deletes '(5.0/9.0) * (fahr-32)'
2ci(   --> Substitutes '(5.0/9.0) * (fahr-32)'
2yi(   --> Yanks '(5.0/9.0) * (fahr-32)'

3di(   --> Deletes '"%3.0f\t%6.1f\n", fahr, ((5.0/9.0) * (fahr-32))'
3ci(   --> Substitutes '"%3.0f\t%6.1f\n", fahr, ((5.0/9.0) * (fahr-32))'
3yi(   --> Yanks '"%3.0f\t%6.1f\n", fahr, ((5.0/9.0) * (fahr-32))'

You can use d% for deleting and y% for yanking.

Place your cursor on the first parenthesis, then press v%y or v%d.