doc: fix match-expressions.adoc to cover all supported match targets

[eytan-starkware]

Summary

Expanded the match expressions documentation to include support for numeric types (u8, u16, u32, u64, u128, i8, i16, i32, i64, i128), bool, and short string literals, in addition to the previously documented enum and felt252 support. Added concrete code examples for integer and boolean matching patterns.

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Type of change

Please check one:

• Bug fix (fixes incorrect behavior)
• New feature
• Performance improvement
• Documentation change with concrete technical impact
• Style, wording, formatting, or typo-only change

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Why is this change needed?

The documentation was incomplete and potentially misleading by stating that only two kinds of match expressions were supported (enum and felt252), when in fact Cairo's match expressions work with a broader range of types including all integer types, booleans, and short string literals. This omission could cause developers to unnecessarily avoid using match expressions with these supported types.

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What was the behavior or documentation before?

The documentation claimed that "Currently two kinds of match expression are supported" and only showed examples for enum and felt252 matching, with no mention of integer types, booleans, or short string literals.

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What is the behavior or documentation after?

The documentation now accurately describes that match expressions support enums, felt252, all integer types (u8-u128, i8-i128), bool, and short string literals, with practical code examples demonstrating integer and boolean matching patterns.

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Related issue or discussion (if any)

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Additional context

This change helps developers understand the full capabilities of Cairo's match expressions, enabling them to write more idiomatic and readable code when working with numeric and boolean values.

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Note

Low Risk
Low risk documentation-only change; the main risk is minor confusion if any listed supported targets diverge from actual compiler behavior.

Overview
Clarifies match-expressions.adoc by replacing the prior “two kinds supported” limitation with a broader Supported match targets section.

Documents matching on numeric integer types and bool with concrete examples, and adds coverage/examples for struct/tuple destructuring, fixed-size array patterns, OR (|) patterns, and nested (recursive) patterns. Adds a small See also section linking to related pattern/expression docs.

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[eytan-starkware]

• doc: fix match-expressions.adoc to cover all supported match targets #9759 👈 (View in Graphite)
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[reviewable-StarkWare]

This change is 

[orizi]

@orizi made 2 comments.
Reviewable status: 0 of 1 files reviewed, 2 unresolved discussions (waiting on eytan-starkware and TomerStarkware).

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docs/reference/src/components/cairo/modules/language_constructs/pages/match-expressions.adoc line 31 at r1 (raw file):

====

== Supported match targets

should probably mention recursive matching as well - but maybe not for this PR.

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docs/reference/src/components/cairo/modules/language_constructs/pages/match-expressions.adoc line 53 at r1 (raw file):

Match expressions also work on `felt252`, integer types (`u8`, `u16`, `u32`, `u64`, `u128`,
`i8`, `i16`, `i32`, `i64`, `i128`), `bool`, and short string literals (which are `felt252` values).

short string literals are simply other ways to write numeric value - of all types - not specifically felt252 but for that reason - should probably not be mentioned here at all.

[TomerStarkware]

@TomerStarkware reviewed 1 file and all commit messages, and made 1 comment.
Reviewable status: all files reviewed, 3 unresolved discussions (waiting on eytan-starkware).

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docs/reference/src/components/cairo/modules/language_constructs/pages/match-expressions.adoc line 57 at r2 (raw file):

[source, cairo]
----
// Match on felt252

I don't think this is different from integers should just be numeric values,
If you still want to keep it, add a 1 case as it is now supported.

[eytan-starkware]

@eytan-starkware made 3 comments.
Reviewable status: 0 of 1 files reviewed, 3 unresolved discussions (waiting on orizi and TomerStarkware).

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docs/reference/src/components/cairo/modules/language_constructs/pages/match-expressions.adoc line 31 at r1 (raw file):

Previously, orizi wrote…

should probably mention recursive matching as well - but maybe not for this PR.

Done.

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docs/reference/src/components/cairo/modules/language_constructs/pages/match-expressions.adoc line 53 at r1 (raw file):

Previously, orizi wrote…

short string literals are simply other ways to write numeric value - of all types - not specifically felt252 but for that reason - should probably not be mentioned here at all.

Done.

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docs/reference/src/components/cairo/modules/language_constructs/pages/match-expressions.adoc line 57 at r2 (raw file):

Previously, TomerStarkware wrote…

I don't think this is different from integers should just be numeric values,
If you still want to keep it, add a 1 case as it is now supported.

Done.

[chatgpt-codex-connector]

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[chatgpt-codex-connector]

Remove fixed-size array match support claim

This section documents fixed-size array patterns in match, but the lowering path still rejects [T; N] as a matched type: create_node_for_patterns only handles numeric, enum, struct, and tuple types, and falls through to MatchDiagnostic::UnsupportedMatchedType for others (crates/cairo-lang-lowering/src/lower/flow_control/create_graph/patterns.rs, around match long_ty). As written, users following this example will hit an E3004 unsupported-type diagnostic instead of a working match.

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[orizi]

@orizi resolved 2 discussions.
Reviewable status: 0 of 1 files reviewed, 2 unresolved discussions (waiting on eytan-starkware and TomerStarkware).