Range patterns

This commit is contained in:
Aleksey Kladov 2018-08-08 15:05:33 +03:00
parent bfb90dc4f1
commit 5e0fbd5964
5 changed files with 89 additions and 22 deletions

View file

@ -143,6 +143,7 @@ Grammar(
"TUPLE_STRUCT_PAT",
"TUPLE_PAT",
"SLICE_PAT",
"RANGE_PAT",
// atoms
"TUPLE_EXPR",

View file

@ -1,16 +1,29 @@
use super::*;
pub(super) fn pattern(p: &mut Parser) {
if let Some(lhs) = atom_pat(p) {
// test range_pat
// fn main() {
// match 92 { 0 ... 100 => () }
// }
if p.at(DOTDOTDOT) {
let m = lhs.precede(p);
p.bump();
atom_pat(p);
m.complete(p, RANGE_PAT);
}
}
}
fn atom_pat(p: &mut Parser) -> Option<CompletedMarker> {
let la0 = p.nth(0);
let la1 = p.nth(1);
if la0 == REF_KW || la0 == MUT_KW
|| (la0 == IDENT && !(la1 == COLONCOLON || la1 == L_PAREN || la1 == L_CURLY)) {
bind_pat(p, true);
return;
return Some(bind_pat(p, true));
}
if paths::is_path_start(p) {
path_pat(p);
return;
return Some(path_pat(p));
}
// test literal_pattern
@ -21,17 +34,22 @@ pub(super) fn pattern(p: &mut Parser) {
// "hello" => (),
// }
// }
if expressions::literal(p).is_some() {
return;
match expressions::literal(p) {
Some(m) => return Some(m),
None => (),
}
match la0 {
let m = match la0 {
UNDERSCORE => placeholder_pat(p),
AMP => ref_pat(p),
L_PAREN => tuple_pat(p),
L_BRACK => slice_pat(p),
_ => p.err_and_bump("expected pattern"),
}
_ => {
p.err_and_bump("expected pattern");
return None;
}
};
Some(m)
}
// test path_part
@ -41,7 +59,7 @@ pub(super) fn pattern(p: &mut Parser) {
// let Bar { .. } = ();
// let Bar(..) = ();
// }
fn path_pat(p: &mut Parser) {
fn path_pat(p: &mut Parser) -> CompletedMarker {
let m = p.start();
paths::expr_path(p);
let kind = match p.current() {
@ -55,7 +73,7 @@ fn path_pat(p: &mut Parser) {
}
_ => PATH_PAT
};
m.complete(p, kind);
m.complete(p, kind)
}
// test tuple_pat_fields
@ -98,7 +116,9 @@ fn struct_pat_fields(p: &mut Parser) {
p.bump();
pattern(p);
}
_ => bind_pat(p, false),
_ => {
bind_pat(p, false);
}
}
if !p.at(R_CURLY) {
p.expect(COMMA);
@ -109,11 +129,11 @@ fn struct_pat_fields(p: &mut Parser) {
// test placeholder_pat
// fn main() { let _ = (); }
fn placeholder_pat(p: &mut Parser) {
fn placeholder_pat(p: &mut Parser) -> CompletedMarker {
assert!(p.at(UNDERSCORE));
let m = p.start();
p.bump();
m.complete(p, PLACEHOLDER_PAT);
m.complete(p, PLACEHOLDER_PAT)
}
// test ref_pat
@ -121,31 +141,31 @@ fn placeholder_pat(p: &mut Parser) {
// let &a = ();
// let &mut b = ();
// }
fn ref_pat(p: &mut Parser) {
fn ref_pat(p: &mut Parser) -> CompletedMarker {
assert!(p.at(AMP));
let m = p.start();
p.bump();
p.eat(MUT_KW);
pattern(p);
m.complete(p, REF_PAT);
m.complete(p, REF_PAT)
}
// test tuple_pat
// fn main() {
// let (a, b, ..) = ();
// }
fn tuple_pat(p: &mut Parser) {
fn tuple_pat(p: &mut Parser) -> CompletedMarker {
assert!(p.at(L_PAREN));
let m = p.start();
tuple_pat_fields(p);
m.complete(p, TUPLE_PAT);
m.complete(p, TUPLE_PAT)
}
// test slice_pat
// fn main() {
// let [a, b, ..] = [];
// }
fn slice_pat(p: &mut Parser) {
fn slice_pat(p: &mut Parser) -> CompletedMarker {
assert!(p.at(L_BRACK));
let m = p.start();
p.bump();
@ -160,7 +180,7 @@ fn slice_pat(p: &mut Parser) {
}
p.expect(R_BRACK);
m.complete(p, SLICE_PAT);
m.complete(p, SLICE_PAT)
}
// test bind_pat
@ -172,7 +192,7 @@ fn slice_pat(p: &mut Parser) {
// let e @ _ = ();
// let ref mut f @ g @ _ = ();
// }
fn bind_pat(p: &mut Parser, with_at: bool) {
fn bind_pat(p: &mut Parser, with_at: bool) -> CompletedMarker {
let m = p.start();
p.eat(REF_KW);
p.eat(MUT_KW);
@ -180,5 +200,5 @@ fn bind_pat(p: &mut Parser, with_at: bool) {
if with_at && p.eat(AT) {
pattern(p);
}
m.complete(p, BIND_PAT);
m.complete(p, BIND_PAT)
}

View file

@ -135,6 +135,7 @@ pub enum SyntaxKind {
TUPLE_STRUCT_PAT,
TUPLE_PAT,
SLICE_PAT,
RANGE_PAT,
TUPLE_EXPR,
ARRAY_EXPR,
PAREN_EXPR,
@ -374,6 +375,7 @@ impl SyntaxKind {
TUPLE_STRUCT_PAT => &SyntaxInfo { name: "TUPLE_STRUCT_PAT" },
TUPLE_PAT => &SyntaxInfo { name: "TUPLE_PAT" },
SLICE_PAT => &SyntaxInfo { name: "SLICE_PAT" },
RANGE_PAT => &SyntaxInfo { name: "RANGE_PAT" },
TUPLE_EXPR => &SyntaxInfo { name: "TUPLE_EXPR" },
ARRAY_EXPR => &SyntaxInfo { name: "ARRAY_EXPR" },
PAREN_EXPR => &SyntaxInfo { name: "PAREN_EXPR" },

View file

@ -0,0 +1,3 @@
fn main() {
match 92 { 0 ... 100 => () }
}

View file

@ -0,0 +1,41 @@
FILE@[0; 47)
FN_ITEM@[0; 46)
FN_KW@[0; 2)
WHITESPACE@[2; 3)
NAME@[3; 7)
IDENT@[3; 7) "main"
PARAM_LIST@[7; 9)
L_PAREN@[7; 8)
R_PAREN@[8; 9)
WHITESPACE@[9; 10)
BLOCK_EXPR@[10; 46)
L_CURLY@[10; 11)
WHITESPACE@[11; 16)
MATCH_EXPR@[16; 44)
MATCH_KW@[16; 21)
WHITESPACE@[21; 22)
LITERAL@[22; 24)
INT_NUMBER@[22; 24) "92"
WHITESPACE@[24; 25)
L_CURLY@[25; 26)
WHITESPACE@[26; 27)
MATCH_ARM@[27; 42)
RANGE_PAT@[27; 36)
LITERAL@[27; 28)
INT_NUMBER@[27; 28) "0"
WHITESPACE@[28; 29)
DOTDOTDOT@[29; 32)
WHITESPACE@[32; 33)
LITERAL@[33; 36)
INT_NUMBER@[33; 36) "100"
WHITESPACE@[36; 37)
FAT_ARROW@[37; 39)
WHITESPACE@[39; 40)
TUPLE_EXPR@[40; 42)
L_PAREN@[40; 41)
R_PAREN@[41; 42)
WHITESPACE@[42; 43)
R_CURLY@[43; 44)
WHITESPACE@[44; 45)
R_CURLY@[45; 46)
WHITESPACE@[46; 47)