From 735a7b4f1879d9e5345ba565183b358aa6b3feee Mon Sep 17 00:00:00 2001 From: Pontus Sjostedt <98153862+pontussjostedt@users.noreply.github.com> Date: Fri, 22 Dec 2023 15:41:22 +0100 Subject: [PATCH] update example in readme (#94) Closes issue #92 --- README.md | 74 ++++++++++++++++++++++++++++++++----------------------- 1 file changed, 43 insertions(+), 31 deletions(-) diff --git a/README.md b/README.md index 755d685..b899afc 100644 --- a/README.md +++ b/README.md @@ -13,39 +13,48 @@ The documentation of the crate is available [here](https://docs.rs/nom_locate/). The crate provide the [`LocatedSpan` struct](https://docs.rs/nom_locate/latest/nom_locate/struct.LocatedSpan.html) that encapsulates the data. Look at the below example and the explanations: ````rust -#[macro_use] extern crate nom; -#[macro_use] extern crate nom_locate; -use nom_locate::LocatedSpan; -type Span<'a> = LocatedSpan<&'a str>; +use nom::bytes::complete::{tag, take_until}; +use nom::IResult; +use nom_locate::{position, LocatedSpan}; +type Span<'a> = LocatedSpan<&'a str>; struct Token<'a> { pub position: Span<'a>, - pub foo: String, - pub bar: String, + pub _foo: &'a str, + pub _bar: &'a str, +} + +fn parse_foobar(s: Span) -> IResult { + let (s, _) = take_until("foo")(s)?; + let (s, pos) = position(s)?; + let (s, foo) = tag("foo")(s)?; + let (s, bar) = tag("bar")(s)?; + + Ok(( + s, + Token { + position: pos, + _foo: foo.fragment(), + _bar: bar.fragment(), + }, + )) } -named!(parse_foobar( Span ) -> Token, do_parse!( - take_until!("foo") >> - position: position!() >> - foo: tag!("foo") >> - bar: tag!("bar") >> - (Token { - position: position, - foo: foo.to_string(), - bar: bar.to_string() - }) -)); - -fn main () { +fn main() { let input = Span::new("Lorem ipsum \n foobar"); let output = parse_foobar(input); let position = output.unwrap().1.position; - assert_eq!(position.location_offset(), 14); - assert_eq!(position.location_line(), 2); - assert_eq!(position.fragment(), &""); + assert_eq!(position, unsafe { + Span::new_from_raw_offset( + 14, // offset + 2, // line + "", // fragment + (), // extra + ) + }); assert_eq!(position.get_column(), 2); } ```` @@ -76,8 +85,8 @@ The output structure of your parser may contain the position as a `Span` (which ````rust struct Token<'a> { pub position: Span<'a>, - pub foo: &'a str, - pub bar: &'a str, + pub _foo: &'a str, + pub _bar: &'a str, } ```` @@ -96,8 +105,8 @@ fn parse_foobar(s: Span) -> IResult { s, Token { position: pos, - foo: foo.fragment, - bar: bar.fragment, + _foo: foo.fragment(), + _bar: bar.fragment(), }, )) } @@ -108,14 +117,17 @@ fn parse_foobar(s: Span) -> IResult { The parser returns a `nom::IResult` (hence the `unwrap().1`). The `position` property contains the `offset`, `line` and `column`. ````rust -fn main () { +fn main() { let input = Span::new("Lorem ipsum \n foobar"); let output = parse_foobar(input); let position = output.unwrap().1.position; - assert_eq!(position, Span { - offset: 14, - line: 2, - fragment: "" + assert_eq!(position, unsafe { + Span::new_from_raw_offset( + 14, // offset + 2, // line + "", // fragment + (), // extra + ) }); assert_eq!(position.get_column(), 2); }