validCashtag top-level constant

String const validCashtag

A cashtag is a $ prefixed ticker-like symbol composed of ASCII letters optionally followed by additional ASCII letters or digits.

Examples that match: $AAPL, $tsla, $BRK1, $GME. Examples that do NOT match: $1, $-AAPL, $$AAPL, $AAPL$BB.

The pattern intentionally mirrors the spirit of validHashtag regarding boundary detection but constrains the body to ticker-like symbols, which is the de-facto convention for cashtags.

Implementation

const validCashtag =
    '($cashtagBoundary)'
    '($cashSigns)'
    r'([A-Za-z][A-Za-z0-9]*)'
    r'(?![A-Za-z0-9])';