Files
a0_basic_app
a1_vehicle
a2_async_sim
ab_glyph
ab_glyph_rasterizer
adler
adler32
agents
aho_corasick
anyhow
approx
aquamarine
ash
atty
bitflags
bytemuck
byteorder
cache_padded
cfg_if
chrono
color_quant
crc32fast
crossbeam_channel
crossbeam_deque
crossbeam_epoch
crossbeam_utils
deflate
draw2d
either
flexi_logger
generic_array
gif
glfw
glfw_sys
glob
image
indoc
itertools
jpeg_decoder
lazy_static
libc
libloading
log
matrixmultiply
memchr
memoffset
miniz_oxide
nalgebra
base
geometry
linalg
third_party
num_complex
num_cpus
num_integer
num_iter
num_rational
num_traits
owned_ttf_parser
paste
png
proc_macro2
proc_macro_error
proc_macro_error_attr
quote
raw_window_handle
rawpointer
rayon
rayon_core
regex
regex_syntax
scoped_threadpool
scopeguard
semver
semver_parser
serde
serde_derive
simba
smawk
spin_sleep
syn
terminal_size
textwrap
thiserror
thiserror_impl
tiff
time
triple_buffer
ttf_parser
typenum
unicode_width
unicode_xid
unindent
vk_sys
weezl
yansi
 1
 2
 3
 4
 5
 6
 7
 8
 9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
use crate::error::{Error, Result};
use proc_macro::token_stream::IntoIter as TokenIter;
use proc_macro::{Spacing, Span, TokenStream, TokenTree};
use std::iter;

pub struct Expr(TokenStream);

pub fn parse(input: &mut TokenIter) -> Result<Expr> {
    #[derive(PartialEq)]
    enum Lookbehind {
        JointColon,
        DoubleColon,
        Other,
    }

    let mut expr = TokenStream::new();
    let mut lookbehind = Lookbehind::Other;
    let mut angle_bracket_depth = 0;

    loop {
        match input.next() {
            Some(TokenTree::Punct(punct)) => {
                let ch = punct.as_char();
                let spacing = punct.spacing();
                expr.extend(iter::once(TokenTree::Punct(punct)));
                lookbehind = match ch {
                    ',' if angle_bracket_depth == 0 => return Ok(Expr(expr)),
                    ':' if lookbehind == Lookbehind::JointColon => Lookbehind::DoubleColon,
                    ':' if spacing == Spacing::Joint => Lookbehind::JointColon,
                    '<' if lookbehind == Lookbehind::DoubleColon => {
                        angle_bracket_depth += 1;
                        Lookbehind::Other
                    }
                    '>' if angle_bracket_depth > 0 => {
                        angle_bracket_depth -= 1;
                        Lookbehind::Other
                    }
                    _ => Lookbehind::Other,
                };
            }
            Some(token) => expr.extend(iter::once(token)),
            None => {
                return Err(Error::new(
                    Span::call_site(),
                    "unexpected end of macro input",
                ))
            }
        }
    }
}

impl Expr {
    pub fn into_tokens(self) -> TokenStream {
        self.0
    }
}