Problem with regex (again)

Hi everyone, I have again a question about a regex.

I am actually working on the Kconfig parsor.

I would like a regex able to catch any line containing for example the word menuconfig, who start with, space, tab or nothing, and end with tab or space.

How can I specify nothing ?

This is the regex table actually I use:

KconfigKeywords = { :config => /[\s]+config[\s]+/,
                                :bool => /[\s]+bool[\s]+/,
                                :dependsOn => /[\s]+depends[\s]+on[\s]+/,
                                :endif => /[\s]+endif[\s]+/,
                                :if => /[\s]+if[\s]+/,
                                :menuconfig => /[\s]+menuconfig[\s]+/,
                                :tristate => /[\s]+tristate[\s]+/,
                                :select => /[\s]+select[\s]+/,
                                :source => /[\s]+source[\s]+/}

/s* matches zero or more whitespace characters.

Tested here:
https://play.crystal-lang.org/#/r/ggm6

Copilot and gpts know the answer :)

Also, the square brackets are unnecesary:
https://play.crystal-lang.org/#/r/ggm7