1.3.0 - Introduces text-slices, and various small improvements

[erezsh]

New features

• Lark can now parse in sections of strings, using TextSlice, as a faster alternative to creating a "copy-slice" with s[i:j]. Learn more
• Added support to match on Tree instances
• When serializing a Lark instance, added the option to include the grammar object (before compilation).
• Added convenience method Tree.find_token()

Bugfixes

• Bugfix of an edge case in Earley related to representation of ambiguity.
• Bugfixes in the standalone parser related to imports
• Bugfix in indenter - now dedents always contain line information
• Various small bugfixes (see PR list below)

Full list of PRs

• Docs: Rephrase v_args() documentation to underline it only applies to Transformer classes by @skepppy in Docs: Rephrase v_args() documentation to underline it only applies to Transformer classes #1458
• Tiny refactor for PR Earley: share nodes created by the scanner with the completer #1451 by @erezsh in Tiny refactor for PR #1451 #1459
• Earley: share nodes created by the scanner with the completer by @chanicpanic in Earley: share nodes created by the scanner with the completer #1451
• Better error in Lark.parse when using on_error when parser!=lalr (issue TypeError: Parser.parse() got an unexpected keyword argument 'on_error' #1311) by @erezsh in Better error in Lark.parse when using on_error when parser!=lalr (issue #1311) #1460
• Fix Symbol.__eq__ to return false when comparing with None by @weaversam8 in Fix Symbol.__eq__ to return false when comparing with None #1481
• Mention internal/external transformers in the documentation by @odanoburu in Mention internal/external transformers in the documentation #1486
• Add Tree.find_token() method by @makukha in Add Tree.find_token() method #1467
• Type Terminal.__init__ by @Liam-DeVoe in Type Terminal.__init__ #1503
• Add guidance on handling comments in languages with significant indentation by @nchammas in Add guidance on handling comments in languages with significant indentation #1502
• [docs] Small fix for PR 1507 by @erezsh in [docs] Small fix for PR 1507 #1508
• Add note on binding power of numeric quantifiers by @414owen in Add note on binding power of numeric quantifiers #1507
• Wrap functools.partial in staticmethod() to add compatibility with Python 3.14 by @hrnciar in Wrap functools.partial in staticmethod() to add compatibility with Python 3.14 #1483
• Fix generic type of Transformer_InPlaceRecursive by @lbhm in Fix generic type of Transformer_InPlaceRecursive #1518
• Added TextSlice; Lark can now parse/lex a text-slice by @erezsh in Added TextSlice; Lark can now parse/lex a text-slice #1452
• Support match on tree by @colmmurphyxyz in Support match on tree #1521
• Docs: Updated link of DSL article to a new version by @erezsh in Docs: Updated link of DSL article to a new version #1529
• better error messages for shift/reduct conflicts by @skogsbaer in better error messages for shift/reduct conflicts #1531
• Serialize Lark.grammar (fixes issue cache option does not work with Reconstructor #1472) by @NasalDaemon in Serialize Lark.grammar (fixes issue #1472) #1506
• Fixes for PR Serialize Lark.grammar (fixes issue #1472) #1506, which adds the option to cache the grammar definition by @erezsh in Fixes for PR #1506, which adds the option to cache the grammar definition #1540
• Bugfix in indenter - now always creating dedents with line information by @erezsh in Bugfix in indenter - now always creating dedents with line information #1547
• Bugfix: issue when unpickling in the standalone parser, due to lingering Token instances by @erezsh in Bugfix: issue when unpickling in the standalone parser, due to lingering Token instances #1553
• Include missing import in standalone parser by @pdeibert in Include missing import in standalone parser #1541
• Version bump (1.3.0) by @erezsh in Version bump (1.3.0) #1554

New Contributors

• @skepppy made their first contribution in Docs: Rephrase v_args() documentation to underline it only applies to Transformer classes #1458
• @weaversam8 made their first contribution in Fix Symbol.__eq__ to return false when comparing with None #1481
• @odanoburu made their first contribution in Mention internal/external transformers in the documentation #1486
• @makukha made their first contribution in Add Tree.find_token() method #1467
• @Liam-DeVoe made their first contribution in Type Terminal.__init__ #1503
• @414owen made their first contribution in Add note on binding power of numeric quantifiers #1507
• @hrnciar made their first contribution in Wrap functools.partial in staticmethod() to add compatibility with Python 3.14 #1483
• @lbhm made their first contribution in Fix generic type of Transformer_InPlaceRecursive #1518
• @colmmurphyxyz made their first contribution in Support match on tree #1521
• @skogsbaer made their first contribution in better error messages for shift/reduct conflicts #1531
• @NasalDaemon made their first contribution in Serialize Lark.grammar (fixes issue #1472) #1506
• @pdeibert made their first contribution in Include missing import in standalone parser #1541

Full Changelog: 1.2.2...1.3.0

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This discussion was created from the release 1.3.0 - Introduces text-slices, and various small improvements.