pub fn parse_hash_expression(input: &str) -> Option<HashExpression>Expand description
Parses hash-algorithm "-" base64-value (CSP3 §2.3.1) from input,
without CSP’s surrounding '...' quotes – callers parsing a
hash-source token strip the quotes first and pass the inner string
here; callers parsing an SRI integrity="" hash token pass it as-is.