re2-20160401-2.fc25.x86_64

RE2 is a C++ library providing a fast, safe, thread-friendly alternative to backtracking regular expression engines like those used in PCRE, Perl, and Python.

Backtracking engines are typically full of features and convenient syntactic sugar but can be forced into taking exponential amounts of time on even small inputs.

In contrast, RE2 uses automata theory to guarantee that regular expression searches run in time linear in the size of the input, at the expense of some missing features (e.g back references and generalized assertions).