chord_pro 0.4.0

A Dart parser for the ChordPro 6 song format. Extracts chords, lyrics, metadata, comments, layout hints and chord diagrams.

0.4.0

Spec-compliance pass against the ChordPro reference parser.

• Breaking: the canonical negation form is now postfix ! — {name-sel!} — matching the ChordPro spec and the reference Perl parser (s/\!$//). Directive.toString emits this form. The previous prefix {name-!sel} and legacy {name+sel} forms continue to be accepted on input for backward compatibility but are now flagged as non-spec.
• Conditional selectors now gate all directives, not just metadata and formatting. Sections with an inactive selector skip their entire body (lines, nested directives, and the section end), per spec ("selection applies to everything in the section, up to and including the final section end directive"). Comments, images, layout breaks, chorus recalls, and {define}/{chord} definitions are likewise suppressed when their selector polarity does not match.
• Add the spec-listed chord qualifiers ^ (alternate for maj), h (half-diminished), and 0 (diminished, literal zero). The pre-existing ø/° glyphs remain as documented non-spec extensions.
• Add ChordPro 6.01 scanner features: \-terminated line continuation (with leading whitespace stripped from the next line) and \uXXXX Unicode escapes anywhere in the source.
• Document explicitly which features are non-spec extensions of this parser (German H, unicode accidentals, ø/°, NC/N.C./N.C, bracket-escapes, mid-lyric directives, legacy selector forms) and which spec features are not yet covered (label="…" parsing, Pango markup, {define} format strings).

0.3.0

• Add selectors: argument to ChordPro.parse / parseSong so callers can activate conditional directives. The same set is forwarded to reduceFormatting, which now honours selector polarity. Matching is case-insensitive.
• Directive.toString emits a postfix ! for negative polarity instead of the legacy +sel form.
• Drop the unused collection dependency.

0.2.0

• Skip # file-comment lines per spec.
• Add sortartist and tag metadata fields.
• Accept spec-form {name-!sel: …} selector negation alongside the legacy +sel form.
• Emit {comment} / {comment_italic} (ci) / {comment_box} (cb) / {highlight} as Line.comment entries.
• Parse {image: …} into a typed ImageDirective exposed as Line.image entries.
• Add Chord.transpose, Song.transposed, and metadata.transpose.
• Recognise {new_page} / {new_physical_page} / {column_break} as Line.layoutBreak entries; capture {columns} / {col} as metadata.columns.
• Add svg and textblock verbatim section kinds.
• Reduce font/size/colour directives into Song.formatting (FormattingSettings keyed by target).
• Recognise x_* custom-extension directives via Directive.isCustomExtension and Song.customExtensions.
• Extend the chord parser to handle German H, unicode ♯/♭, minor variants (mi, -), half-diminished ø, diminished °, and NC/N.C. no-chord markers.

0.1.0

• Intial