pattern-wishcast 0.0.1-pre.7

Pattern types emulation for conditional variants using conditional never types
Documentation 
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// SPDX-FileCopyrightText: 2025 LunNova
//
// SPDX-License-Identifier: MIT

//! Test that basic supported pattern syntax works correctly

use pattern_wishcast::pattern_wishcast;

// <generated by cargo-derive-doc>
// Macro expansions:
//   pub enum Value<P : PatternFields>
//   pub struct ValueType
//   impl  PatternFields for ValueType
//   pub struct BasicPatternsType
//   impl  PatternFields for BasicPatternsType
//   pub struct TuplePatternsType
//   impl  PatternFields for TuplePatternsType
//   pub struct WildcardPatternType
//   impl  PatternFields for WildcardPatternType
//   pub type BasicPatterns = Value <BasicPatternsType>
//   pub type TuplePatterns = Value <TuplePatternsType>
//   pub type WildcardPattern = Value <WildcardPatternType>
//   impl  BasicPatterns
//   impl  WildcardPattern
//   pub const test_subtyping_basicpatterns_wildcardpattern: test::TestDescAndFn
//    fn test_subtyping_basicpatterns_wildcardpattern ()
//   pub const test_basic_pattern_syntax: test::TestDescAndFn
//   pub fn main () -> ()
// </generated by cargo-derive-doc>
pattern_wishcast! {
	enum Value is <P: PatternFields> = {
		Number { value: i32 },
		Text { content: String },
		Flag,
		DebugInfo,
	};

	// These should all work fine:
	type BasicPatterns = Value is Number { .. } | Text { .. } | Flag;
	type TuplePatterns = Value is Number(_) | Text(_) | Flag;
	type WildcardPattern = Value is _;

	#[derive(SubtypingRelation(upcast=to_flex, downcast=try_to_strict))]
	impl BasicPatterns : WildcardPattern;
}

#[test]
fn test_basic_pattern_syntax() {
	// Test that all the pattern syntaxes compile and work
	let num = BasicPatterns::Number { value: 42 };
	let flex = num.to_flex();

	match flex.try_to_strict() {
		Ok(_) => {} // Expected - should convert back
		Err(_) => panic!("Should be able to convert back to strict"),
	}
}