How do you run a vim command that is the text inside a buffer?

Question

For example lets say this text is inside buffer

%s/a/b/gI

How do I run that as a vim command, without typing it inside the vim command line.

Regards

Answer 1

In command mode:

You yank the text, say if it was on its own line

y$

then type

:

then

<ctrl-r> "

Answer 2

You can yank the text--even multiple lines--then type:

:@"

(That's colon, at symbol, double quote.)

In fact you could yank it to a named register, such as a, and do:

:@a

See:

:help :@