Joscha
b009a9c4ec
I noticed that programs like '{} would parse correctly while '{ } would
expect an inner element. This was because the leading space was actually
part of the element parser, which is a violation of the (as of yet
unspoken) rule that parsers should not parse surrounding whitespace.
Because whitespace whas treated differently from everywhere else and
because this implementation was wrong, I decided to reimplement it,
abstracting the concept of things separated by other things with
optional trailing things. I did this in such a way that surrounding
whitespace is not touched.
68 lines
1.3 KiB
Rust
68 lines
1.3 KiB
Rust
use crate::span::{HasSpan, Span};
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use super::{Expr, Ident, Separated, Space};
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// TODO Make table patterns recursive
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#[derive(Debug, Clone)]
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pub enum TablePatternElem {
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/// `foo`
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Positional(Ident),
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/// `foo: bar`
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///
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/// Structure: `name s0 : s1 ident`
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Named {
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name: Ident,
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s0: Space,
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s1: Space,
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ident: Ident,
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span: Span,
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},
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}
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impl HasSpan for TablePatternElem {
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fn span(&self) -> Span {
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match self {
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TablePatternElem::Positional(ident) => ident.span(),
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TablePatternElem::Named { span, .. } => *span,
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}
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}
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}
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/// `{ foo, bar: baz }`
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///
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/// Structure: `{ s0 elems s1 }`
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#[derive(Debug, Clone)]
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pub struct TablePattern {
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pub s0: Space,
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pub elems: Separated<TablePatternElem, (Space, Space), Space>,
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pub s1: Space,
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pub span: Span,
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}
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impl HasSpan for TablePattern {
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fn span(&self) -> Span {
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self.span
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}
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}
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/// - `{ foo, bar: baz } = a`
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/// - `local { foo, bar: baz } = a`
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///
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/// Structure: `local pattern s0 = s1 value`
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#[derive(Debug, Clone)]
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pub struct TableDestr {
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pub local: Option<Space>,
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pub pattern: TablePattern,
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pub s0: Space,
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pub s1: Space,
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pub value: Box<Expr>,
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pub span: Span,
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}
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impl HasSpan for TableDestr {
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fn span(&self) -> Span {
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self.span
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}
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}
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