Changes: Evaluate an expression in any mode

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Tip 524 Printable Monobook Previous Next

created August 3, 2003 · complexity basic · author Yakov Lerner · version 6.0

The <CTRL-R>= things evaluates the expression. For example:

<CTRL-R>=12+34<CR>

<CTRL-R>= works in insert mode and in command mode. I felt it more convenient if <CTRL-R>= did the same thing in normal mode too.

I have this in my vimrc:

map <CTRL-R>= :echo

Now <CTRL-R>=123*456<CR> evaluates expressions for me in all 3 modes: normal mode, insert mode, and command mode. In fact I found it much more convenient to do casual calculations using <CTRl-R>= in normal mode than in any other mode.

Be warned: when typing <CTRL-R>= in normal mode, don't make long pause before '='. <CTRL-R> alone means 'redo' in normal mode. Vim is very smart, and figures the difference between single <CTRL-R> (which is 'redo') and the mapped sequence <CTRL-R>= (which is remapped). The 'timeoutlen' option controls this difference. The default value of 'timeoutlen' option is very convenient.

This is an expansion of Using Vim as calculator.

References[]

Comments[]

To get the behavior like i_CTRL-r in normal mode, use @=. For example, in normal mode, @='dd'<CR> will delete the current line just as if you had pressed dd in normal mode.

:help @

For more information. You can also do things like

:let @a = 'dd'

and then press @a in normal mode. This does the same thing.

@@ Line 12: / Line 12: @@
 |category2=
 }}
-The &lt;CTRL-R&gt;= things evaluates the expression. For example:
+The <CTRL-R>= things evaluates the expression. For example:
+<pre>
- &lt;CTRL-R&gt;=12+34&lt;cr&gt;
+<CTRL-R>=12+34<CR>
+</pre>
-&lt;CTRL-R&gt;= works in insert mode and in command mode. I felt it more convenient if &lt;CTRL-R&gt;= did the same thing in normal mode too.
+<CTRL-R>= works in insert mode and in command mode. I felt it more convenient if <CTRL-R>= did the same thing in normal mode too.
-I have this in my .vimrc:
+I have this in my [[vimrc]]:
+<pre>
- map &lt;CTRL-R&gt;= :echo
+map <CTRL-R>= :echo
+</pre>
-Now &lt;CTRL-R&gt;=123*456&lt;CR&gt; evaluates expressions for me in all 3 modes: normal mode, insert mode, and command mode. In fact I found it much more convenient to do casual calculations using &lt;CTRl-R&gt;= in normal mode than in any other mode.
+Now <CTRL-R>=123*456<CR> evaluates expressions for me in all 3 modes: normal mode, insert mode, and command mode. In fact I found it much more convenient to do casual calculations using <CTRl-R>= in normal mode than in any other mode.
-Be warned: when typing &lt;CTRL-R&gt;= in normal mode, don't make long pause before '='. &lt;CTRL-R&gt; alone means 'redo' in normal mode. Vim is very smart, and figures the difference between single &lt;CTRL-R&gt; (which is 'redo') and the mapped sequence &lt;CTRL-R&gt;= (which is remapped). The 'timeoutlen' option controls this difference. The default value of 'timeoutlen' option is very convenient.
+Be warned: when typing <CTRL-R>= in normal mode, don't make long pause before '='. <CTRL-R> alone means 'redo' in normal mode. Vim is very smart, and figures the difference between single <CTRL-R> (which is 'redo') and the mapped sequence <CTRL-R>= (which is remapped). The 'timeoutlen' option controls this difference. The default value of 'timeoutlen' option is very convenient.
 This is an expansion of [[VimTip73|Using Vim as calculator]].
@@ Line 33: / Line 37: @@
 ==Comments==
-To get the behavior like i_CTRL-r in normal mode, use @=. For example, in normal mode, @='dd'&lt;cr&gt; will delete the current line just as if you had pressed dd in normal mode.
+To get the behavior like i_CTRL-r in normal mode, use @=. For example, in normal mode, @='dd'<CR> will delete the current line just as if you had pressed dd in normal mode.
 *{{help|@}}