+use std::{+    collections::BTreeMap,+    convert::TryInto as _,+    env, fmt, fs,+    path::{Path, PathBuf},+};++use chrono::{Datelike as _, TimeZone as _, Utc};+use glob::glob;+use regex::Regex;++#[derive(Debug, Copy, Clone, PartialEq, Eq)]+struct Date {+    year: u32,+    month: u32,+}++impl Date {+    fn months_since(self, other: Date) -> Option<u32> {+        let self_chrono = Utc.ymd(self.year.try_into().unwrap(), self.month, 1);+        let other_chrono = Utc.ymd(other.year.try_into().unwrap(), other.month, 1);+        let duration_since = self_chrono.signed_duration_since(other_chrono);+        let days_since = duration_since.num_days();

+use std::{+    collections::BTreeMap,+    convert::TryInto as _,+    env, fmt, fs,+    path::{Path, PathBuf},+};++use chrono::{Datelike as _, TimeZone as _, Utc};+use glob::glob;+use regex::Regex;++#[derive(Debug, Copy, Clone, PartialEq, Eq)]+struct Date {+    year: u32,+    month: u32,

+use std::{+    collections::BTreeMap,+    convert::TryInto as _,+    env, fmt, fs,+    path::{Path, PathBuf},+};++use chrono::{Datelike as _, TimeZone as _, Utc};+use glob::glob;+use regex::Regex;++#[derive(Debug, Copy, Clone, PartialEq, Eq)]+struct Date {+    year: u32,+    month: u32,+}++impl Date {+    fn months_since(self, other: Date) -> Option<u32> {+        let self_chrono = Utc.ymd(self.year.try_into().unwrap(), self.month, 1);+        let other_chrono = Utc.ymd(other.year.try_into().unwrap(), other.month, 1);+        let duration_since = self_chrono.signed_duration_since(other_chrono);+        let days_since = duration_since.num_days();+        if days_since < 0 {+            None+        } else {+            Some(days_since.try_into().unwrap())+        }+    }+}++impl fmt::Display for Date {+    fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {+        write!(f, "{:04}-{:02}", self.year, self.month)+    }+}++fn make_date_regex() -> Regex {+    Regex::new(

+use std::{+    collections::BTreeMap,+    convert::TryInto as _,+    env, fmt, fs,+    path::{Path, PathBuf},+};++use chrono::{Datelike as _, TimeZone as _, Utc};+use glob::glob;+use regex::Regex;++#[derive(Debug, Copy, Clone, PartialEq, Eq)]+struct Date {+    year: u32,+    month: u32,+}++impl Date {+    fn months_since(self, other: Date) -> Option<u32> {+        let self_chrono = Utc.ymd(self.year.try_into().unwrap(), self.month, 1);+        let other_chrono = Utc.ymd(other.year.try_into().unwrap(), other.month, 1);+        let duration_since = self_chrono.signed_duration_since(other_chrono);+        let days_since = duration_since.num_days();+        if days_since < 0 {+            None+        } else {+            Some(days_since.try_into().unwrap())+        }+    }+}++impl fmt::Display for Date {+    fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {+        write!(f, "{:04}-{:02}", self.year, self.month)+    }+}++fn make_date_regex() -> Regex {+    Regex::new(

+use std::{+    collections::BTreeMap,+    convert::TryInto as _,+    env, fmt, fs,+    path::{Path, PathBuf},+};++use chrono::{Datelike as _, TimeZone as _, Utc};+use glob::glob;+use regex::Regex;++#[derive(Debug, Copy, Clone, PartialEq, Eq)]+struct Date {+    year: u32,+    month: u32,+}++impl Date {+    fn months_since(self, other: Date) -> Option<u32> {+        let self_chrono = Utc.ymd(self.year.try_into().unwrap(), self.month, 1);+        let other_chrono = Utc.ymd(other.year.try_into().unwrap(), other.month, 1);+        let duration_since = self_chrono.signed_duration_since(other_chrono);+        let days_since = duration_since.num_days();+        if days_since < 0 {+            None+        } else {+            Some(days_since.try_into().unwrap())+        }+    }+}++impl fmt::Display for Date {+    fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {+        write!(f, "{:04}-{:02}", self.year, self.month)+    }+}++fn make_date_regex() -> Regex {+    Regex::new(+        r"(?x) # insignificant whitespace mode+        <!--\s*+        date:\s*+        (?P<y>\d{4}) # year+        -+        (?P<m>\d{2}) # month+        \s*-->",+    )+    .unwrap()+}++fn collect_dates_from_file(date_regex: &Regex, text: &str) -> Vec<(usize, Date)> {+    let mut dates = vec![];+    let mut line = 1;+    let mut end_of_last_cap = 0;+    for (byte_range, date) in date_regex.captures_iter(&text).map(|cap| {+        (+            cap.get(0).unwrap().range(),+            Date {+                year: cap["y"].parse().unwrap(),+                month: cap["m"].parse().unwrap(),+            },+        )+    }) {+        for chr in text[end_of_last_cap..byte_range.end].chars() {

+use std::{+    collections::BTreeMap,+    convert::TryInto as _,+    env, fmt, fs,+    path::{Path, PathBuf},+};++use chrono::{Datelike as _, TimeZone as _, Utc};+use glob::glob;+use regex::Regex;++#[derive(Debug, Copy, Clone, PartialEq, Eq)]+struct Date {+    year: u32,+    month: u32,

+use std::{+    collections::BTreeMap,+    convert::TryInto as _,+    env, fmt, fs,+    path::{Path, PathBuf},+};++use chrono::{Datelike as _, TimeZone as _, Utc};+use glob::glob;+use regex::Regex;++#[derive(Debug, Copy, Clone, PartialEq, Eq)]+struct Date {+    year: u32,+    month: u32,+}++impl Date {+    fn months_since(self, other: Date) -> Option<u32> {+        let self_chrono = Utc.ymd(self.year.try_into().unwrap(), self.month, 1);+        let other_chrono = Utc.ymd(other.year.try_into().unwrap(), other.month, 1);+        let duration_since = self_chrono.signed_duration_since(other_chrono);+        let days_since = duration_since.num_days();

 if [ "$MAX_LINE_LENGTH" == "" ]; then fi  if [ "$1" == "" ]; then-  files=( src/**/*.md )+  files=( src/**.md )

 # Request for stabilization +**NOTE**: this page is about stabilizing language features.+For stabilizing library features, see [Stabilizing a library feature].

 even on an `unstable` function, if that function is called from another Furthermore this attribute is needed to mark an intrinsic as callable from `rustc_const_stable` functions. +## Stabilizing a library feature++To stabilize a feature, follow these steps:++0. Ask a **@T-libs** member to start an FCP on the tracking issue and wait for+   the FCP to complete (with `disposition-merge`).+1. Change `#[unstable]` to `#[stable(since = "version")]`.+   `version` should be the *current nightly*, i.e. stable+2. You can see which version is+   currently nightly [on Forge](https://forge.rust-lang.org/#current-release-versions).+2. Remove `#![feature]` from any test or doc-test for this API. If the feature is used in the+   compiler or tools, remove it from there as well.+3. If applicable, change `#[rustc_const_unstable]` to `#[rustc_const_stable(since = "version")]`.

 even on an `unstable` function, if that function is called from another Furthermore this attribute is needed to mark an intrinsic as callable from `rustc_const_stable` functions. +## Stabilizing a library feature++To stabilize a feature, follow these steps:++0. Ask a **@T-libs** member to start an FCP on the tracking issue and wait for+   the FCP to complete (with `disposition-merge`).+1. Change `#[unstable]` to `#[stable(since = "version")]`.+   `version` should be the *current nightly*, i.e. stable+2. You can see which version is+   currently nightly [on Forge](https://forge.rust-lang.org/#current-release-versions).+2. Remove `#![feature]` from any test or doc-test for this API. If the feature is used in the+   compiler or tools, remove it from there as well.+3. If applicable, change `#[rustc_const_unstable]` to `#[rustc_const_stable(since = "version")]`.+4. Open a PR against `rust-lang/rust`

 even on an `unstable` function, if that function is called from another Furthermore this attribute is needed to mark an intrinsic as callable from `rustc_const_stable` functions. +## Stabilizing a library feature++To stabilize a feature, follow these steps:++0. Ask a **@T-libs** member to start an FCP on the tracking issue and wait for+   the FCP to complete (with `disposition-merge`).+1. Change `#[unstable]` to `#[stable(since = "version")]`.+   `version` should be the *current nightly*, i.e. stable+2. You can see which version is+   currently nightly [on Forge](https://forge.rust-lang.org/#current-release-versions).+2. Remove `#![feature]` from any test or doc-test for this API. If the feature is used in the

 even on an `unstable` function, if that function is called from another Furthermore this attribute is needed to mark an intrinsic as callable from `rustc_const_stable` functions. +## Stabilizing a library feature++To stabilize a feature, follow these steps:++0. Ask a **@T-libs** member to start an FCP on the tracking issue and wait for+   the FCP to complete (with `disposition-merge`).+1. Change `#[unstable]` to `#[stable(since = "version")]`.+   `version` should be the *current nightly*, i.e. stable+2. You can see which version is+   currently nightly [on Forge](https://forge.rust-lang.org/#current-release-versions).

 if [ "$MAX_LINE_LENGTH" == "" ]; then fi  if [ "$1" == "" ]; then-  files=( src/**/*.md )+  files=( src/**.md )

 even on an `unstable` function, if that function is called from another Furthermore this attribute is needed to mark an intrinsic as callable from `rustc_const_stable` functions. +## Stabilizing a library feature++To stabilize a feature, follow these steps:++0. Ask a **@T-libs** to start an FCP on the tracking issue and wait for the FCP to complete (with `disposition-merge`).

 even on an `unstable` function, if that function is called from another Furthermore this attribute is needed to mark an intrinsic as callable from `rustc_const_stable` functions. +## Stabilizing a library feature++To stabilize a feature, follow these steps:++0. Ask a **@T-libs** to start an FCP on the tracking issue and wait for the FCP to complete (with `disposition-merge`).