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use crate::ident::{Ident, ModuleName};
use crate::literal::Literal;
use crate::node::Spanned;
/// A pattern in Elm source code.
///
/// Patterns appear in function arguments, case branches, let destructuring, and
/// lambda arguments.
#[cfg_attr(feature = "serde", derive(serde::Serialize, serde::Deserialize))]
#[derive(Clone, Debug, PartialEq, Eq)]
pub enum Pattern {
/// Wildcard pattern: `_`
Anything,
/// Variable binding: `x`, `name`
Var(Ident),
/// Literal pattern: `42`, `"hello"`, `'c'`
Literal(Literal),
/// Unit pattern: `()`
Unit,
/// Tuple pattern: `( a, b )` or `( a, b, c )`
Tuple(Vec<Spanned<Pattern>>),
/// Constructor pattern, possibly qualified: `Just x`, `Maybe.Nothing`
Constructor {
module_name: ModuleName,
name: Ident,
args: Vec<Spanned<Pattern>>,
},
/// Record destructuring pattern: `{ name, age }`
Record(Vec<Spanned<Ident>>),
/// Cons pattern: `x :: xs`
Cons {
head: Box<Spanned<Pattern>>,
tail: Box<Spanned<Pattern>>,
},
/// List pattern: `[ x, y, z ]`
List(Vec<Spanned<Pattern>>),
/// As pattern: `_ as name`, `(x, y) as point`
As {
pattern: Box<Spanned<Pattern>>,
name: Spanned<Ident>,
},
/// Parenthesized pattern: `( pattern )`
Parenthesized(Box<Spanned<Pattern>>),
/// Hex literal pattern: `0xFF`
Hex(i64),
}