mirror of https://github.com/rust-lang/rust
29 lines
657 B
Rust
29 lines
657 B
Rust
//@ force-host
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//@ no-prefer-dynamic
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#![crate_type = "proc-macro"]
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#![feature(proc_macro_tracked_env)]
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extern crate proc_macro;
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use proc_macro::TokenStream;
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use proc_macro::tracked_env::var;
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#[proc_macro]
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pub fn generate_const(input: TokenStream) -> TokenStream {
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let the_const = match var("THE_CONST") {
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Ok(x) if x == "12" => {
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"const THE_CONST: u32 = 12;"
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}
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_ => {
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"const THE_CONST: u32 = 0;"
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}
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};
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let another = if var("ANOTHER").is_ok() {
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"const ANOTHER: u32 = 1;"
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} else {
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"const ANOTHER: u32 = 2;"
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};
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format!("{the_const}{another}").parse().unwrap()
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}
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