Merge pull request #16 from rodrimati1992/0.2patch

0.2.14 release

.github/workflows/rust.yml

@@ -27,6 +27,15 @@ jobs:
         cd "${{github.workspace}}/const_format/"
         cargo test --features "testing"
 
+    - uses: actions/checkout@v2
+    - name: ci-stable
+      # apparently github hadn't updated stable by 2021-03-27?
+      if: ${{ matrix.rust == 'beta' }}
+      run: |
+        cargo update
+        cd "${{github.workspace}}/const_format/"
+        cargo test --features "testing const_generics"
+
 
     - uses: actions/checkout@v2
     - name: ci-nighly

Changelog.md

@@ -2,6 +2,15 @@ This is the changelog,summarising changes in each version(some minor changes may
 
 # 0.2 
 
+### 0.2.14
+
+Fixed a few documentation issues.
+
+Made the `const_format::fmt` API that uses const generics unconditional, since const generics were stabilized in late 2020 and the `fmt` API requires the nightly compiler.
+
+Repurposed the "const_generics" feature to generate less code in the `concatcp` and `formatcp` macros,
+by moving some of their implementation to a function that uses const generics.
+
 ### 0.2.13
 
 Fixed the assertion macros not to use `std::panic`, using `core::panic` instead, since `core::panic` changed to allow passing a non-literal `&'static str` argument.

README.md

@@ -269,14 +269,9 @@ An optimization that requires a few additional nightly features,
 allowing the `as_bytes_alt` methods and `slice_up_to_len_alt` methods to run 
 in constant time, rather than linear time proportional to the truncated part of the slice.
 
-- "const_generics":
-Enables impls that use const generics, currently only used for ergonomics.
-Use this when const generics are usable in stable Rust.
-
-- "nightly_const_generics":
-Enables impls that use const generics, currently only used for ergonomics.
-This requires a nightly Rust compiler.
-
+- "const_generics": Requires Rust 1.51.0.
+Uses const generics in the implementation of the [`concatcp`] and [`formatcp`]
+macros to output less code.
 
 # No-std support
 

const_format/Cargo.toml

@@ -1,6 +1,6 @@
 [package]
 name = "const_format"
-version = "0.2.13"
+version = "0.2.14"
 authors = ["rodrimati1992 <rodrimatt1985@gmail.com>"]
 edition = "2018"
 license = "Zlib"
@@ -24,7 +24,7 @@ travis-ci = { repository =  "rodrimati1992/const_format_crates/" }
 default = []
 const_generics = []
 nightly_const_generics = ["const_generics"]
-fmt = []
+fmt = ["const_generics"]
 derive = ["fmt", "const_format_proc_macros/derive"]
 assert = ["fmt"]
 constant_time_as_str = ["fmt"]
@@ -37,7 +37,7 @@ docsrs = []
 all = ["fmt", "derive", "constant_time_as_str", "nightly_const_generics", "assert", "docsrs"]
 
 [dependencies.const_format_proc_macros]
-version = "=0.2.8"
+version = "=0.2.14"
 path = "../const_format_proc_macros"
 
 [dev-dependencies]

const_format/src/const_debug_derive.rs

@@ -51,16 +51,6 @@
 /// When this attribute is used it disables the default implementation
 /// that uses the type parameters generically.
 ///
-/// ### `#[cdeb(crate = "foo::bar")]`
-///
-/// The path to the `const_format` crate, useful if you want to reexport the ConstDebug macro,
-/// or rename the const_format crate in the Cargo.toml .
-///
-/// Example of renaming the `const_format` crate in the Cargo.toml file:
-/// ```toml
-/// cfmt = {version = "0.*", package = "const_format"}
-/// ```
-///
 /// Example:
 /// 
 /// ```rust
@@ -77,11 +67,21 @@
 /// In this example, there's exactly three impls of 
 /// the `const_debug_fmt` method and [`FormatMarker`] trait.
 ///
+/// ### `#[cdeb(crate = "foo::bar")]`
+///
+/// The path to the `const_format` crate, useful if you want to reexport the ConstDebug macro,
+/// or rename the `const_format` crate in the Cargo.toml .
+///
+/// Example of renaming the `const_format` crate in the Cargo.toml file:
+/// ```toml
+/// cfmt = {version = "0.*", package = "const_format"}
+/// ```
+///
 /// # Field attributes
 ///
 /// ### `#[cdeb(ignore)]`
 ///
-/// Ignoes the field, pretending that it doesn't exist.
+/// Ignores the field, pretending that it doesn't exist.
 ///
 /// ### `#[cdeb(with = "module::function")]`
 ///
@@ -195,7 +195,7 @@
 /// 
 /// This example demonstrates the `#[cdeb(impls)]` attribute,
 /// a workaround for deriving this trait for generic types,
-/// specifying a list of impls of types that uncnoditionally implement debug formatting
+/// specifying a list of impls of types that unconditionally implement debug formatting
 /// 
 /// ```rust
 /// #![feature(const_mut_refs)]

const_format/src/const_generic_concatcp.rs

@@ -0,0 +1,22 @@
+//! Reimplements some stuff from concatcp to be const generic instead of macro generated
+
+use crate::pmr::{LenAndArray, PArgument, PVariant};
+
+#[doc(hidden)]
+pub const fn __priv_concatenate<const LEN: usize>(input: &[PArgument]) -> LenAndArray<[u8; LEN]> {
+    let mut out = LenAndArray {
+        len: 0,
+        array: [0u8; LEN],
+    };
+
+    crate::__for_range! { outer_i in 0..input.len() =>
+        let current = &input[outer_i];
+
+        match current.elem {
+            PVariant::Str(s) => crate::__write_pvariant!(str, current, s => out),
+            PVariant::Int(int) => crate::__write_pvariant!(int, current, int => out),
+        }
+    }
+
+    out
+}

const_format/src/fmt.rs

@@ -53,7 +53,7 @@
 //! - Named, from constant (eg: `formatc!("{FOO}")`):
 //! Uses the `FOO` constant from the enclosing scope.
 //!
-//! - Named, from locals (eg: `formatc!("{foo}")`):
+//! - Named, from locals (eg: `writec!(writable, "{foo}")`):
 //! Uses the `foo` local variable from the enclosing scope,
 //! only usable with the [`writec`] macro.
 //!
@@ -187,7 +187,7 @@
 //!     impl[U,] Foo<u32, U>;
 //!     impl[U,] Foo<&str, U>;
 //!
-//!     pub const fn const_debug_fmt(&mut self, f: &mut Formatter<'_>) -> Result<(), Error> {
+//!     pub const fn const_debug_fmt(&self, f: &mut Formatter<'_>) -> Result<(), Error> {
 //!         let mut f = f.debug_struct("Foo");
 //!
 //!         // PWrapper is a wrapper for std types, which defines the formatter methods for them.

const_format/src/fmt/str_writer.rs

@@ -455,8 +455,6 @@ impl StrWriter {
     }
 }
 
-#[cfg_attr(feature = "docsrs", doc(cfg(feature = "const_generics")))]
-#[cfg(feature = "const_generics")]
 impl<const N: usize> StrWriter<[u8; N]> {
     /// Casts a `&StrWriter<[u8; N]>` to a `&StrWriter<[u8]>`,
     /// for calling methods defined on `StrWriter<[u8]>` (most of them).

const_format/src/lib.rs

@@ -257,13 +257,9 @@
 //! allowing the `as_bytes_alt` methods and `slice_up_to_len_alt` methods to run
 //! in constant time, rather than linear time proportional to the truncated part of the slice.
 //!
-//! "const_generics":
-//! Enables impls that use const generics, currently only used for ergonomics.
-//! Use this when const generics are usable in stable Rust.
-//!
-//! "nightly_const_generics":
-//! Enables impls that use const generics, currently only used for ergonomics.
-//! This requires a nightly Rust compiler.
+//! - "const_generics": Requires Rust 1.51.0.
+//! Uses const generics in the implementation of the [`concatcp`] and [`formatcp`]
+//! macros to output less code.
 //!
 //!
 //!
@@ -353,6 +349,9 @@ pub mod panicking;
 
 mod pargument;
 
+#[cfg(feature = "const_generics")]
+mod const_generic_concatcp;
+
 #[cfg_attr(feature = "docsrs", doc(cfg(feature = "fmt")))]
 #[cfg(feature = "fmt")]
 pub mod utils;
@@ -421,6 +420,9 @@ pub mod pmr {
         result::Result::{self, Err, Ok},
     };
 
+    #[cfg(feature = "const_generics")]
+    pub use crate::const_generic_concatcp::__priv_concatenate;
+
     #[cfg(feature = "fmt")]
     pub use crate::{
         fmt::{ComputeStrLength, Error, Formatter, StrWriter, StrWriterMut, ToResult},

const_format/src/macros/fmt_macros.rs

@@ -63,9 +63,10 @@ macro_rules! concatcp {
 
 #[doc(hidden)]
 #[macro_export]
+#[cfg(not(feature = "const_generics"))]
 macro_rules! __concatcp_inner {
     ($variables:ident) => {{
-        const ARR_LEN: usize = $variables.0;
+        const ARR_LEN: usize = $crate::pmr::PArgument::calc_len($variables);
 
         const CONCAT_ARR: &$crate::pmr::LenAndArray<[u8; ARR_LEN]> = {
             use $crate::{__write_pvariant, pmr::PVariant};
@@ -75,7 +76,7 @@ macro_rules! __concatcp_inner {
                 array: [0u8; ARR_LEN],
             };
 
-            let input = $variables.1;
+            let input = $variables;
 
             $crate::__for_range! { outer_i in 0..input.len() =>
                 let current = &input[outer_i];
@@ -100,6 +101,28 @@ macro_rules! __concatcp_inner {
     }};
 }
 
+#[doc(hidden)]
+#[macro_export]
+#[cfg(feature = "const_generics")]
+macro_rules! __concatcp_inner {
+    ($variables:ident) => {{
+        const ARR_LEN: usize = $crate::pmr::PArgument::calc_len($variables);
+
+        const CONCAT_ARR: &$crate::pmr::LenAndArray<[u8; ARR_LEN]> =
+            &$crate::pmr::__priv_concatenate($variables);
+
+        #[allow(clippy::transmute_ptr_to_ptr)]
+        const CONCAT_STR: &str = unsafe {
+            // This transmute truncates the length of the array to the amound of written bytes.
+            let slice =
+                $crate::pmr::transmute::<&[u8; ARR_LEN], &[u8; CONCAT_ARR.len]>(&CONCAT_ARR.array);
+
+            $crate::pmr::transmute::<&[u8], &str>(slice)
+        };
+        CONCAT_STR
+    }};
+}
+
 ////////////////////////////////////////////////////////////////////////////////
 
 /// Formats constants of primitive types into a `&'static str`
@@ -120,7 +143,7 @@ macro_rules! __concatcp_inner {
 /// - Use constants from scope as arguments: `formatcp!("{FOO}")`,
 /// equivalent to the [`format_args_implicits` RFC]
 ///
-/// - Use Debug-like formatting (eg: `formatcp!("{:?}", "hello" ):
+/// - Use Debug-like formatting (eg: `formatcp!("{:?}", "hello" )`:
 /// Similar to how Debug formatting in the standard library works,
 /// except that it does not escape unicode characters.`
 ///

const_format/src/marker_traits/format_marker.rs

@@ -113,23 +113,20 @@ pub trait FormatMarker {
 /// used as the [`Kind`] associated type  in [`FormatMarker`].
 ///
 /// [`Kind`]: ./trait.FormatMarker.html#associatedtype.Kind
-/// [`FormatMarker`]: ./trait.FormatMarker.html
 ///
 pub struct IsArrayKind<T>(PhantomData<T>);
 
 /// Marker type for the remaining standard library types,,
 /// used as the [`Kind`] associated type  in [`FormatMarker`].
 ///
 /// [`Kind`]: ./trait.FormatMarker.html#associatedtype.Kind
-/// [`FormatMarker`]: ./trait.FormatMarker.html
 ///
 pub struct IsStdKind;
 
 /// Marker type for non-standard library types,
 /// used as the [`Kind`] associated type  in [`FormatMarker`].
 ///
 /// [`Kind`]: ./trait.FormatMarker.html#associatedtype.Kind
-/// [`FormatMarker`]: ./trait.FormatMarker.html
 ///
 pub struct IsNotStdKind;
 
@@ -168,6 +165,8 @@ macro_rules! std_kind_impls {
 /// `T` is `<R as FormatMarker>::This`:
 /// The `R` type after removing all layers of references.
 ///
+/// `R`: a type that implements [`FormatMarker`].
+///
 /// # Coerce Method
 ///
 /// The `coerce` method is what does the conversion from a `&T` depending on
@@ -179,12 +178,6 @@ macro_rules! std_kind_impls {
 ///
 /// - [`IsNotStdKind`]: the reference is simply returned as a `&T`.
 ///
-/// [`IsArrayKind`]: ./struct.IsArrayKind.html
-/// [`IsStdKind`]: ./struct.IsStdKind.html
-/// [`IsNotStdKind`]: ./struct.IsNotStdKind.html
-///
-/// [`PWrapper`]: ../struct.PWrapper.html
-///
 #[allow(clippy::type_complexity)]
 pub struct IsAFormatMarker<K, T: ?Sized, R: ?Sized>(
     PhantomData<(
@@ -249,17 +242,6 @@ impl<T: ?Sized, R: ?Sized> IsAFormatMarker<IsNotStdKind, T, R> {
 
 /////////////////////////////////////////////////////////////////////////////
 
-macro_rules! array_impls {
-    ($($len:literal),* $(,)* ) => (
-        $(
-            impl<T> FormatMarker for [T; $len] {
-                type Kind = IsArrayKind<T>;
-                type This = Self;
-            }
-        )*
-    )
-}
-
 std_kind_impls! {
     i8, u8,
     i16, u16,
@@ -283,11 +265,9 @@ impl<R: ?Sized> IsAFormatMarker<IsStdKind, str, R> {
     }
 }
 
-array_impls! {
-    0,1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,
-    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,
-    48,49,50,51,52,53,54,55,56,57,58,59,60,61,62,63,
+impl<T, const N: usize> FormatMarker for [T; N] {
+    type Kind = IsArrayKind<T>;
+    type This = Self;
 }
 
 impl<T> FormatMarker for [T] {

const_format/src/marker_traits/write_marker.rs

@@ -163,6 +163,8 @@ where
 /// `T` is `<R as WriteMarker>::This`:
 /// The `R` type after removing all layers of references.
 ///
+/// `R`: A type that implements `WriteMarker`.
+///
 /// # Coerce Method
 ///
 /// The `coerce` method is what does the conversion from a `&mut T`

const_format/src/pargument.rs

@@ -14,6 +14,20 @@ pub struct PArgument {
     pub fmt_flags: FormattingFlags,
 }
 
+impl PArgument {
+    /// Calculates the length of the string after adding up all the PArguments
+    pub const fn calc_len(mut args: &[PArgument]) -> usize {
+        let mut sum = 0;
+
+        while let [curr, rem @ ..] = args {
+            args = rem;
+            sum += curr.fmt_len;
+        }
+
+        sum
+    }
+}
+
 #[doc(hidden)]
 pub enum PVariant {
     Str(&'static str),

const_format/tests/fmt_tests/str_writer_methods.rs

@@ -337,7 +337,7 @@ fn write_str_debug() {
             while let Err(_) = w.write_str_range_debug(ALL_ASCII, gen_range()) {}
             let end = w.len();
             start + 1..end - 1
-        };
+        }
 
         #[cfg(not(miri))]
         const ITERATIONS: usize = 1000;

const_format_proc_macros/Cargo.toml

@@ -1,6 +1,6 @@
 [package]
 name = "const_format_proc_macros"
-version = "0.2.8"
+version = "0.2.14"
 authors = ["rodrimati1992 <rodrimatt1985@gmail.com>"]
 edition = "2018"
 license = "Zlib"