How can you match the prefix of a string with a regex?

I currently have the following, but would like to know if there's a better way. 

/^a(b(b(r(e(v(i(a(t(i(o(n)?)?)?)?)?)?)?)?)?)?)?$/

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This is only a toy problem so non-regex solutions need not apply :) (unless they're interesting)

Brad

In reply to Abbreviation regex? by bsb

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