Allow lifting local failure to global failure

[ghost]

PR type

• Bug fix (non-breaking change which fixes an issue): no
• New feature (non-breaking change which adds functionality): yes
• Breaking change (fix or feature that would cause existing functionality to change): no
• Documentation change: no

Prerequisites

• I have read the CONTRIBUTING.md document: yes
• I have updated the documentation accordingly: no (tbd)
• I have added tests to cover my changes: yes

Description

This is a proposed implementation of #593. It defines a new operator # in the PEGJS grammar that converts any local failure to a global one. The bytecode generator and JavaScript generator have been updated accordingly.

Example:

VariableDefninition = VarToken __ name:#Identifier __ #"=" __ #Expression

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[ghost]

Seems like I forgot to re-enable the ESLint task locally and missed the warnings. I'll try to fix the issues if this gets approved. In the meantime, back to messing my new language. :smile:

[futagoza]

1. It's probably best to use a more descriptive name instead of global_fail, like fatal_fallback
2. Same as 1, only for context.failGlobally (e.g. context.fatalFallback)
3. Have you tested this with a complex grammar?
4. Documentation needs updating (only syntax documentation I think)
5. If you're comfortable with TypeScript, can you update the typings, otherwise I'll do it if this is merged

[ghost]

@futagoza No problem, I'll update the documentation and the typings as well either today or tomorrow. Will also add some more tests to be sure everything works correctly.

[StoneCypher]

Oh man, I wish this had gotten merged

It's really powerful, really difficult, slightly buggy, and the person who made it left github, so there's no way to ask for help 😦

This was super important. It didn't get merged because two underscores weren't added, and because someone wanted to know why a log comment had a space on it? And the bugs weren't noticed?