Add support for zero-copy parsing

.github/workflows/rust.yml

@@ -2,9 +2,9 @@ name: Rust
 
 on:
   push:
-    branches: [ master ]
+    branches: [ master, zero-copy ]
   pull_request:
-    branches: [ master ]
+    branches: [ master, zero-copy ]
 
 env:
   CARGO_TERM_COLOR: always
@@ -34,5 +34,5 @@ jobs:
             toolchain: nightly
             override: true
             components: rustfmt, clippy
-      - name: Run cargo check
+      - name: Run cargo test
         run: cargo test --verbose --all-features

Cargo.toml

@@ -2,7 +2,7 @@
 name = "chumsky"
 version = "0.8.0"
 description = "A parser library for humans with powerful error recovery"
-authors = ["Joshua Barretto <[email protected]>"]
+authors = ["Joshua Barretto <[email protected]>", "Elijah Hartvigsen <[email protected]", "Jakob Wiesmore <[email protected]>"]
 repository = "https://github.com/zesterer/chumsky"
 license = "MIT"
 keywords = ["parser", "combinator", "token", "language", "syntax"]
@@ -14,24 +14,41 @@ exclude = [
 ]
 
 [features]
-default = ["ahash", "std", "spill-stack"]
-# Use `ahash` instead of the standard hasher for maintaining sets of expected inputs
-# (Also used if `std` is disabled)
-ahash = []
+default = ["std", "spill-stack", "memoization"]
 # Integrate with the standard library
 std = []
-# Enable nightly-only features like better compiler diagnostics
+# Enable nightly-only features like better compiler diagnostics and a Parser impl for ! (the never type)
 nightly = []
 # Allows deeper recursion by dynamically spilling stack state on to the heap
 spill-stack = ["stacker", "std"]
+# Allows parser memoisation, speeding up heavily back-tracking parsers and allowing left recursion
+memoization = []
 
 [dependencies]
-# Used if `std` is disabled.
-# Provides `ahash` for the corresponding feature as it uses it by default.
-# Due to https://github.com/rust-lang/cargo/issues/1839, this can't be optional
-hashbrown = "0.11"
+hashbrown = "0.13"
 stacker = { version = "0.1", optional = true }
+# Enables regex combinators
+regex = { version = "1.7", optional = true }
 
 [dev-dependencies]
-ariadne = "0.1.2"
-pom = "3.0"
+ariadne = "0.1.5"
+pom = "3.2"
+nom = "7.1"
+serde_json = { version = "1.0", features = ["preserve_order"] }
+criterion = "0.4.0"
+pest = "2.5"
+pest_derive = "2.5"
+sn = "0.1"
+logos = "0.12"
+
+[[bench]]
+name = "json"
+harness = false
+
+[[bench]]
+name = "lex"
+harness = false
+
+[[bench]]
+name = "parser"
+harness = false

README.md

@@ -41,7 +41,7 @@ enum Instr {
     Loop(Vec<Self>),
 }
 
-fn parser() -> impl Parser<char, Vec<Instr>, Error = Simple<char>> {
+fn parser<'a>() -> impl Parser<'a, &'a str, Vec<Instr>> {
     recursive(|bf| choice((
         just('<').to(Instr::Left),
         just('>').to(Instr::Right),
@@ -51,7 +51,8 @@ fn parser() -> impl Parser<char, Vec<Instr>, Error = Simple<char>> {
         just('.').to(Instr::Write),
         bf.delimited_by(just('['), just(']')).map(Instr::Loop),
     ))
-        .repeated())
+        .repeated()
+        .collect())
 }
 ```
 

benches/json.pest

@@ -0,0 +1,35 @@
+WHITESPACE = _{ " " | "\t" | "\r" | "\n" }
+
+object = {
+    "{" ~ "}" |
+    "{" ~ pair ~ ("," ~ pair)* ~ "}"
+}
+pair = { string ~ ":" ~ value }
+
+array = {
+    "[" ~ "]" |
+    "[" ~ value ~ ("," ~ value)* ~ "]"
+}
+
+value = _{ object | array | string | number | boolean | null }
+
+boolean = { "true" | "false" }
+
+null = { "null" }
+
+string = ${ "\"" ~ inner ~ "\"" }
+inner = @{ char* }
+char = {
+    !("\"" | "\\") ~ ANY
+    | "\\" ~ ("\"" | "\\" | "/" | "b" | "f" | "n" | "r" | "t")
+    | "\\" ~ ("u" ~ ASCII_HEX_DIGIT{4})
+}
+
+number = @{
+    "-"?
+    ~ ("0" | ASCII_NONZERO_DIGIT ~ ASCII_DIGIT*)
+    ~ ("." ~ ASCII_DIGIT*)?
+    ~ (^"e" ~ ("+" | "-")? ~ ASCII_DIGIT+)?
+}
+
+json = _{ SOI ~ (object | array) ~ EOI }