doc/go1.13: document changes to gofmt, go/* libs, and fix entry for text/scanner
Change-Id: I2230a97c681406f248b7f2fff45dd80a4b54a4b3
Reviewed-on: https://go-review.googlesource.com/c/go/+/183357
Reviewed-by: Ian Lance Taylor <iant@golang.org>
diff --git a/doc/go1.13.html b/doc/go1.13.html
index 5655b06..e2099ce 100644
--- a/doc/go1.13.html
+++ b/doc/go1.13.html
@@ -91,9 +91,9 @@
<p>
These language changes were implemented by changes to the compiler, and corresponding internal changes to the library
- packages <code><a href="https://golang.org/pkg/go/scanner">go/scanner</a></code> and
- <code><a href="https://golang.org/pkg/text/scanner">text/scanner</a></code> (number literals),
- and <code><a href="https://golang.org/pkg/go/types">go/types</a></code> (signed shift counts).
+ packages <code><a href="#go/scanner">go/scanner</a></code> and
+ <code><a href="#text/scanner">text/scanner</a></code> (number literals),
+ and <code><a href="#go/types">go/types</a></code> (signed shift counts).
</p>
<p>
@@ -191,6 +191,22 @@
introduced in ARM v8.1.
</p>
+<h3 id="gofmt">gofmt</h3>
+
+<p>
+ <code>gofmt</code> (and with that <code>go fmt</code>) now canonicalizes
+ number literal prefixes and exponents to use lower-case letters, but
+ leaves hexadecimal digits alone. This improves readability when using the new octal prefix
+ (<code>0O</code> becomes <code>0o</code>), and the rewrite is applied consistently.
+ <code>gofmt</code> now also removes unnecessary leading zeroes from a decimal integer
+ imaginary literal. (For backwards-compatibility, an integer imaginary literal
+ starting with <code>0</code> is considered a decimal, not an octal number.
+ Removing superfluous leading zeroes avoids potential confusion.)
+ For instance, <code>0B1010</code>, <code>0XabcDEF</code>, <code>0O660</code>,
+ <code>1.2E3</code>, and <code>01i</code> become <code>0b1010</code>, <code>0xabcDEF</code>,
+ <code>0o660</code>, <code>1.2e3</code>, and <code>1i</code> after applying <code>gofmt</code>.
+</p>
+
<h2 id="runtime">Runtime</h2>
<p><!-- CL 161477 -->
@@ -338,7 +354,28 @@
type attribute, code will now be interperted as <a href="https://html.spec.whatwg.org/multipage/scripting.html#the-script-element:module-script-2">JavaScript module script</a>.
</p>
-</dl><!-- html/template -->
+ </dl><!-- html/template -->
+
+<dl id="go/scanner"><dt><a href="/pkg/go/scanner/">go/scanner</a></dt>
+ <dd>
+ <p><!-- CL 175218 -->
+ The scanner has been updated to recognize the new Go number literals, specifically
+ binary literals with <code>0b</code>/<code>0B</code> prefix, octal literals with <code>0o</code>/<code>0O</code> prefix,
+ and floating-point numbers with hexadecimal mantissa. The imaginary suffix <code>i</code> may now be used with any number
+ literal, and underscores may used as digit separators for grouping.
+ See the <a href="#language">Changes to the language</a> for details.
+ </p>
+
+ </dl><!-- go/scanner -->
+
+<dl id="go/types"><dt><a href="/pkg/go/types/">go/types</a></dt>
+ <dd>
+ <p>
+ The type-checker has been updated to follow the new rules for integer shifts.
+ See the <a href="#language">Changes to the language</a> for details.
+ </p>
+
+</dl><!-- go/types -->
<dl id="log"><dt><a href="/pkg/log/">log</a></dt>
<dd>
@@ -537,9 +574,13 @@
<dl id="text/scanner"><dt><a href="/pkg/text/scanner/">text/scanner</a></dt>
<dd>
- <p><!-- CL 163079 -->
- The new <a href="/pkg/text/scanner/#AllowNumberbars"><code>AllowNumberbars</code></a>
- mode allows number literals to contain underbars as digit separators.
+ <p><!-- CL 183077 -->
+ The scanner has been updated to recognize the new Go number literals, specifically
+ binary literals with <code>0b</code>/<code>0B</code> prefix, octal literals with <code>0o</code>/<code>0O</code> prefix,
+ and floating-point numbers with hexadecimal mantissa.
+ Also, the new <a href="/pkg/text/scanner/#AllowDigitSeparators"><code>AllowDigitSeparators</code></a>
+ mode allows number literals to contain underscores as digit separators (off by default for backwards-compatibility).
+ See the <a href="#language">Changes to the language</a> for details.
</p>
</dl><!-- text/scanner -->
