Rewrite regex word boundaries as unicode-safe lookarounds

Converts each word-boundary escape in a pattern into (?<![[:alpha:]]) or (?![[:alpha:]]), depending on whether the boundary opens or closes a token. Called from .load_observations_ontology.

Usage

.fix_word_boundaries(pattern)

Arguments

pattern

Character. A regular expression, possibly containing word-boundary escapes.

Value

Character. The pattern with each boundary rewritten as a lookaround.