From 5e20a29b4fdc8a2d442d1093681b396dcb4b816b Mon Sep 17 00:00:00 2001 From: Robin Krahl Date: Tue, 7 Jan 2020 11:18:04 +0000 Subject: Add structopt dependency in version 0.3.7 This patch series replaces argparse with structopt in the argument handling code. As a first step, we need structopt as a dependency. Import subrepo structopt/:structopt at efbdda4753592e27bc430fb01f7b9650b2f3174d Import subrepo bitflags/:bitflags at 30668016aca6bd3b02c766e8347e0b4080d4c296 Import subrepo clap/:clap at 784524f7eb193e35f81082cc69454c8c21b948f7 Import subrepo heck/:heck at 093d56fbf001e1506e56dbfa38631d99b1066df1 Import subrepo proc-macro-error/:proc-macro-error at 6c4cfe79a622c5de8ae68557993542be46eacae2 Import subrepo proc-macro2/:proc-macro2 at d5d48eddca4566e5438e8a2cbed4a74e049544de Import subrepo quote/:quote at 727436c6c137b20f0f34dde5d8fda2679b9747ad Import subrepo rustversion/:rustversion at 0c5663313516263059ce9059ef81fc7a1cf655ca Import subrepo syn-mid/:syn-mid at 5d3d85414a9e6674e1857ec22a87b96e04a6851a Import subrepo syn/:syn at e87c27e87f6f4ef8919d0372bdb056d53ef0d8f3 Import subrepo textwrap/:textwrap at abcd618beae3f74841032aa5b53c1086b0a57ca2 Import subrepo unicode-segmentation/:unicode-segmentation at 637c9874c4fe0c205ff27787faf150a40295c6c3 Import subrepo unicode-width/:unicode-width at 3033826f8bf05e82724140a981d5941e48fce393 Import subrepo unicode-xid/:unicode-xid at 4baae9fffb156ba229665b972a9cd5991787ceb7 --- syn-mid/examples/const_fn/Cargo.toml | 16 ++++++++++++++++ syn-mid/examples/const_fn/lib.rs | 31 +++++++++++++++++++++++++++++++ 2 files changed, 47 insertions(+) create mode 100644 syn-mid/examples/const_fn/Cargo.toml create mode 100644 syn-mid/examples/const_fn/lib.rs (limited to 'syn-mid/examples/const_fn') diff --git a/syn-mid/examples/const_fn/Cargo.toml b/syn-mid/examples/const_fn/Cargo.toml new file mode 100644 index 0000000..d823e76 --- /dev/null +++ b/syn-mid/examples/const_fn/Cargo.toml @@ -0,0 +1,16 @@ +[package] +name = "const_fn" +version = "0.0.0" +authors = ["Taiki Endo "] +edition = "2018" +publish = false + +[lib] +proc-macro = true +path = "lib.rs" + +[dependencies] +proc-macro2 = "1.0" +quote = "1.0" +syn = "1.0" +syn-mid = { version = "0.4", path = "../..", features = ["clone-impls"] } diff --git a/syn-mid/examples/const_fn/lib.rs b/syn-mid/examples/const_fn/lib.rs new file mode 100644 index 0000000..29255f2 --- /dev/null +++ b/syn-mid/examples/const_fn/lib.rs @@ -0,0 +1,31 @@ +#![warn(rust_2018_idioms)] + +extern crate proc_macro; + +use proc_macro::TokenStream; +use proc_macro2::TokenStream as TokenStream2; +use quote::quote; +use syn_mid::ItemFn; + +/// An attribute for easy generation of a const function with conditional compilations. +#[proc_macro_attribute] +pub fn const_fn(args: TokenStream, function: TokenStream) -> TokenStream { + assert!(!args.is_empty(), "requires an argument"); + + let mut function = syn::parse_macro_input!(function as ItemFn); + let mut const_function = function.clone(); + + if function.constness.is_some() { + function.constness = None; + } else { + const_function.constness = Some(Default::default()); + } + + let args = TokenStream2::from(args); + TokenStream::from(quote! { + #[cfg(not(#args))] + #function + #[cfg(#args)] + #const_function + }) +} -- cgit v1.2.1