feat(fixer_v2): Hole Pattern Syntax for Pattern Matching

[notJoon]

Description

A hole pattern is a special syntax used in pattern matching that acts as a placeholder or "wildcard" in a pattern. Think of it as a variable that can match and capture different parts of code while searching through source code.

// Pattern with holes
if :[[condition]] {
    :[[body]]
}

// Can match code like:
if x > 0 {
    return true
}

// Or:
if isValid(user) {
    doSomething()
}

Key Changes

1. Added support for typed hole patterns with format :[[name:type]]
2. Implemented quantifier support for hole patterns (*, +, ?)
3. Enhanced lexer to properly parse and tokenize new pattern syntax
4. Added hole configuration system to manage pattern types and quantifiers
5. Updated parser to handle the new hole types and configurations
6. Added comprehensive test coverage for new features

New Pattern Syntax

Syntax	Description	Example	Notes
:[name]	Basic hole pattern	:[var]	Matches any content
:[[name]]	Long-form hole pattern	:[[expr]]	Same as basic, but with double brackets
:[[name:identifier]]	Identifier-typed hole	:[[var:identifier]]	Matches only valid identifiers
:[[name:block]]	Block-typed hole	:[[body:block]]	Matches code blocks
:[[name:whitespace]]	Whitespace-typed hole	:[[ws:whitespace]]	Matches whitespace
:[[name:expression]]	Expression-typed hole	:[[expr:expression]]	Matches expressions

Quantifiers

Quantifier	Description	Example
*	Zero or more	:[[stmt:block]]*
+	One or more	:[[expr:expression]]+
?	Zero or one	:[[ws:whitespace]]?

Example Usage

// Before
if :[condition] { :[body] }

// After - with types and quantifiers
if :[[cond:expression]] {
    :[[stmt:block]]*
}

Next Steps

Future improvements could include:

• Implementing actual pattern matching logic for each hole type
• Adding pattern validation based on types
• Enhancing error reporting for invalid patterns
• Adding more specialized hole types for specific use cases

Related Issue

#111