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---
source: crates/ruff_python_parser/tests/fixtures.rs
input_file: crates/ruff_python_parser/resources/inline/err/irrefutable_case_pattern.py
---
## AST
```
Module(
ModModule {
node_index: NodeIndex(None),
range: 0..317,
body: [
Match(
StmtMatch {
node_index: NodeIndex(None),
range: 0..61,
subject: Name(
ExprName {
node_index: NodeIndex(None),
range: 6..7,
id: Name("x"),
ctx: Load,
},
),
cases: [
MatchCase {
range: 13..26,
node_index: NodeIndex(None),
pattern: MatchAs(
PatternMatchAs {
node_index: NodeIndex(None),
range: 18..21,
pattern: None,
name: Some(
Identifier {
id: Name("var"),
range: 18..21,
node_index: NodeIndex(None),
},
),
},
),
guard: None,
body: [
Expr(
StmtExpr {
node_index: NodeIndex(None),
range: 23..26,
value: EllipsisLiteral(
ExprEllipsisLiteral {
node_index: NodeIndex(None),
range: 23..26,
},
),
},
),
],
},
MatchCase {
range: 50..61,
node_index: NodeIndex(None),
pattern: MatchValue(
PatternMatchValue {
node_index: NodeIndex(None),
range: 55..56,
value: NumberLiteral(
ExprNumberLiteral {
node_index: NodeIndex(None),
range: 55..56,
value: Int(
2,
),
},
),
},
),
guard: None,
body: [
Expr(
StmtExpr {
node_index: NodeIndex(None),
range: 58..61,
value: EllipsisLiteral(
ExprEllipsisLiteral {
node_index: NodeIndex(None),
range: 58..61,
},
),
},
),
],
},
],
},
),
Match(
StmtMatch {
node_index: NodeIndex(None),
range: 62..102,
subject: Name(
ExprName {
node_index: NodeIndex(None),
range: 68..69,
id: Name("x"),
ctx: Load,
},
),
cases: [
MatchCase {
range: 75..86,
node_index: NodeIndex(None),
pattern: MatchAs(
PatternMatchAs {
node_index: NodeIndex(None),
range: 80..81,
pattern: None,
name: None,
},
),
guard: None,
body: [
Expr(
StmtExpr {
node_index: NodeIndex(None),
range: 83..86,
value: EllipsisLiteral(
ExprEllipsisLiteral {
node_index: NodeIndex(None),
range: 83..86,
},
),
},
),
],
},
MatchCase {
range: 91..102,
node_index: NodeIndex(None),
pattern: MatchValue(
PatternMatchValue {
node_index: NodeIndex(None),
range: 96..97,
value: NumberLiteral(
ExprNumberLiteral {
node_index: NodeIndex(None),
range: 96..97,
value: Int(
2,
),
},
),
},
),
guard: None,
body: [
Expr(
StmtExpr {
node_index: NodeIndex(None),
range: 99..102,
value: EllipsisLiteral(
ExprEllipsisLiteral {
node_index: NodeIndex(None),
range: 99..102,
},
),
},
),
],
},
],
},
),
Match(
StmtMatch {
node_index: NodeIndex(None),
range: 125..222,
subject: Name(
ExprName {
node_index: NodeIndex(None),
range: 131..132,
id: Name("x"),
ctx: Load,
},
),
cases: [
MatchCase {
range: 138..160,
node_index: NodeIndex(None),
pattern: MatchAs(
PatternMatchAs {
node_index: NodeIndex(None),
range: 143..155,
pattern: Some(
MatchAs(
PatternMatchAs {
node_index: NodeIndex(None),
range: 143..147,
pattern: None,
name: Some(
Identifier {
id: Name("var1"),
range: 143..147,
node_index: NodeIndex(None),
},
),
},
),
),
name: Some(
Identifier {
id: Name("var2"),
range: 151..155,
node_index: NodeIndex(None),
},
),
},
),
guard: None,
body: [
Expr(
StmtExpr {
node_index: NodeIndex(None),
range: 157..160,
value: EllipsisLiteral(
ExprEllipsisLiteral {
node_index: NodeIndex(None),
range: 157..160,
},
),
},
),
],
},
MatchCase {
range: 211..222,
node_index: NodeIndex(None),
pattern: MatchValue(
PatternMatchValue {
node_index: NodeIndex(None),
range: 216..217,
value: NumberLiteral(
ExprNumberLiteral {
node_index: NodeIndex(None),
range: 216..217,
value: Int(
2,
),
},
),
},
),
guard: None,
body: [
Expr(
StmtExpr {
node_index: NodeIndex(None),
range: 219..222,
value: EllipsisLiteral(
ExprEllipsisLiteral {
node_index: NodeIndex(None),
range: 219..222,
},
),
},
),
],
},
],
},
),
Match(
StmtMatch {
node_index: NodeIndex(None),
range: 223..316,
subject: Name(
ExprName {
node_index: NodeIndex(None),
range: 229..230,
id: Name("x"),
ctx: Load,
},
),
cases: [
MatchCase {
range: 236..264,
node_index: NodeIndex(None),
pattern: MatchOr(
PatternMatchOr {
node_index: NodeIndex(None),
range: 241..259,
patterns: [
MatchValue(
PatternMatchValue {
node_index: NodeIndex(None),
range: 241..253,
value: Attribute(
ExprAttribute {
node_index: NodeIndex(None),
range: 241..253,
value: Name(
ExprName {
node_index: NodeIndex(None),
range: 241..245,
id: Name("enum"),
ctx: Load,
},
),
attr: Identifier {
id: Name("variant"),
range: 246..253,
node_index: NodeIndex(None),
},
ctx: Load,
},
),
},
),
MatchAs(
PatternMatchAs {
node_index: NodeIndex(None),
range: 256..259,
pattern: None,
name: Some(
Identifier {
id: Name("var"),
range: 256..259,
node_index: NodeIndex(None),
},
),
},
),
],
},
),
guard: None,
body: [
Expr(
StmtExpr {
node_index: NodeIndex(None),
range: 261..264,
value: EllipsisLiteral(
ExprEllipsisLiteral {
node_index: NodeIndex(None),
range: 261..264,
},
),
},
),
],
},
MatchCase {
range: 305..316,
node_index: NodeIndex(None),
pattern: MatchValue(
PatternMatchValue {
node_index: NodeIndex(None),
range: 310..311,
value: NumberLiteral(
ExprNumberLiteral {
node_index: NodeIndex(None),
range: 310..311,
value: Int(
2,
),
},
),
},
),
guard: None,
body: [
Expr(
StmtExpr {
node_index: NodeIndex(None),
range: 313..316,
value: EllipsisLiteral(
ExprEllipsisLiteral {
node_index: NodeIndex(None),
range: 313..316,
},
),
},
),
],
},
],
},
),
],
},
)
```
## Semantic Syntax Errors
|
1 | match x:
2 | case var: ... # capture pattern
| ^^^ Syntax Error: name capture `var` makes remaining patterns unreachable
3 | case 2: ...
4 | match x:
|
|
3 | case 2: ...
4 | match x:
5 | case _: ...
| ^ Syntax Error: wildcard makes remaining patterns unreachable
6 | case 2: ... # wildcard pattern
7 | match x:
|
|
6 | case 2: ... # wildcard pattern
7 | match x:
8 | case var1 as var2: ... # as pattern with irrefutable left-hand side
| ^^^^ Syntax Error: name capture `var1` makes remaining patterns unreachable
9 | case 2: ...
10 | match x:
|
|
9 | case 2: ...
10 | match x:
11 | case enum.variant | var: ... # or pattern with irrefutable part
| ^^^ Syntax Error: name capture `var` makes remaining patterns unreachable
12 | case 2: ...
|
|
9 | case 2: ...
10 | match x:
11 | case enum.variant | var: ... # or pattern with irrefutable part
| ^^^^^^^^^^^^^^^^^^ Syntax Error: alternative patterns bind different names
12 | case 2: ...
|