time_macros/
to_tokens.rs

1use std::num::NonZeroU16;
2
3use proc_macro::{Group, Ident, Literal, Punct, Span, TokenStream, TokenTree};
4
5/// Turn a type into a [`TokenStream`].
6pub(crate) trait ToTokenStream: Sized {
7    fn append_to(self, ts: &mut TokenStream);
8}
9
10pub(crate) trait ToTokenTree: Sized {
11    fn into_token_tree(self) -> TokenTree;
12}
13
14impl<T: ToTokenTree> ToTokenStream for T {
15    fn append_to(self, ts: &mut TokenStream) {
16        ts.extend([self.into_token_tree()])
17    }
18}
19
20impl ToTokenTree for bool {
21    fn into_token_tree(self) -> TokenTree {
22        let lit = if self { "true" } else { "false" };
23        TokenTree::Ident(Ident::new(lit, Span::mixed_site()))
24    }
25}
26
27impl ToTokenStream for TokenStream {
28    fn append_to(self, ts: &mut TokenStream) {
29        ts.extend(self)
30    }
31}
32
33impl ToTokenTree for TokenTree {
34    fn into_token_tree(self) -> TokenTree {
35        self
36    }
37}
38
39impl ToTokenTree for &str {
40    fn into_token_tree(self) -> TokenTree {
41        TokenTree::Literal(Literal::string(self))
42    }
43}
44
45impl ToTokenTree for NonZeroU16 {
46    fn into_token_tree(self) -> TokenTree {
47        quote_group! {{
48            unsafe { ::core::num::NonZeroU16::new_unchecked(#(self.get())) }
49        }}
50    }
51}
52
53macro_rules! impl_for_tree_types {
54    ($($type:ty)*) => {$(
55        impl ToTokenTree for $type {
56            fn into_token_tree(self) -> TokenTree {
57                TokenTree::from(self)
58            }
59        }
60    )*};
61}
62impl_for_tree_types![Ident Literal Group Punct];
63
64macro_rules! impl_for_int {
65    ($($type:ty => $method:ident)*) => {$(
66        impl ToTokenTree for $type {
67            fn into_token_tree(self) -> TokenTree {
68                TokenTree::from(Literal::$method(self))
69            }
70        }
71    )*};
72}
73impl_for_int! {
74    i8 => i8_unsuffixed
75    u8 => u8_unsuffixed
76    u16 => u16_unsuffixed
77    i32 => i32_unsuffixed
78    u32 => u32_unsuffixed
79}
time_macros/to_tokens.rs

time_macros/
to_tokens.rs
