how to write only one pattern to exchange two strings in two-ways in vim

xxx <=> zzz

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Original text:

xxxyyyzzz

Run command:

:s/???/???/

It becomes:

zzzyyyxxx

Run t开发者_高级运维he same command above:

:s/???/???/

Back to the original text:

xxxyyyzzz

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just like toggle case(~)

aBCdeFg <=> AbcDEfG

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Take a look at this: Can I substitute multiple items in a single regular expression in VIM or Perl?

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Try this:

:s/(...)(yyy)(...)/\3\2\1/

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You could always write your own macro. I'm assuming a macro for this specific example would not be helpful to you, but I could post one if you want.