From cca7879dce86a1050e3e408136b24cd2585d9aaf Mon Sep 17 00:00:00 2001 From: Mark McGranaghan Date: Tue, 27 Dec 2016 07:41:08 -0800 Subject: [PATCH] Add note about len and [] operating on bytes Fixes #148. --- examples/string-functions/string-functions.go | 26 ++++++---- .../string-functions/string-functions.hash | 4 +- public/string-functions | 48 +++++++++++-------- 3 files changed, 45 insertions(+), 33 deletions(-) diff --git a/examples/string-functions/string-functions.go b/examples/string-functions/string-functions.go index 6ac0d3d..eea809a 100644 --- a/examples/string-functions/string-functions.go +++ b/examples/string-functions/string-functions.go @@ -14,10 +14,12 @@ var p = fmt.Println func main() { // Here's a sample of the functions available in - // `strings`. Note that these are all functions from the - // package, not methods on the string object itself. - // This means that we need pass the string in question - // as the first argument to the function. + // `strings`. Since these are functions from the + // package, not methods on the string object itself, + // we need pass the string in question as the first + // argument to the function. You can find more + // functions in the [`strings`](http://golang.org/pkg/strings/) + // package docs. p("Contains: ", s.Contains("test", "es")) p("Count: ", s.Count("test", "t")) p("HasPrefix: ", s.HasPrefix("test", "te")) @@ -32,12 +34,16 @@ func main() { p("ToUpper: ", s.ToUpper("test")) p() - // You can find more functions in the [`strings`](http://golang.org/pkg/strings/) - // package docs. - - // Not part of `strings` but worth mentioning here are - // the mechanisms for getting the length of a string - // and getting a character by index. + // Not part of `strings`, but worth mentioning here, are + // the mechanisms for getting the length of a string in + // bytes and getting a byte by index. p("Len: ", len("hello")) p("Char:", "hello"[1]) } + +// Note that `len` and indexing above work at the byte level. +// Go uses UTF-8 encoded strings, so this is often useful +// as-is. If you're working with potentially multi-byte +// characters you'll want to use encoding-aware operations. +// See [strings, bytes, runes and characters in Go](https://blog.golang.org/strings) +// for more information. diff --git a/examples/string-functions/string-functions.hash b/examples/string-functions/string-functions.hash index c4a0d65..93ae1ea 100644 --- a/examples/string-functions/string-functions.hash +++ b/examples/string-functions/string-functions.hash @@ -1,2 +1,2 @@ -d7150ce50772abdaf827082093613134cb05e08f -Gkc5rDaeaN +17aa523bbd606fa0b624fae44b89812d46330755 +Lf5_Zbg6or diff --git a/public/string-functions b/public/string-functions index 8438e99..30b2914 100644 --- a/public/string-functions +++ b/public/string-functions @@ -41,7 +41,7 @@ to give you a sense of the package.

- + 
package main
@@ -90,10 +90,12 @@ it a lot below.

Here’s a sample of the functions available in -strings. Note that these are all functions from the -package, not methods on the string object itself. -This means that we need pass the string in question -as the first argument to the function.

+strings. Since these are functions from the +package, not methods on the string object itself, +we need pass the string in question as the first +argument to the function. You can find more +functions in the strings +package docs.

@@ -118,24 +120,12 @@ as the first argument to the function.

-

You can find more functions in the strings -package docs.

+

Not part of strings, but worth mentioning here, are +the mechanisms for getting the length of a string in +bytes and getting a byte by index.

- - - - - - - - -

Not part of strings but worth mentioning here are -the mechanisms for getting the length of a string -and getting a character by index.

- - - + 
    p("Len: ", len("hello"))
     p("Char:", "hello"[1])
@@ -145,6 +135,22 @@ and getting a character by index.

           
         
         
+        
+          
+            
Note that len and indexing above work at the byte level.
+Go uses UTF-8 encoded strings, so this is often useful
+as-is. If you’re working with potentially multi-byte
+characters you’ll want to use encoding-aware operations.
+See strings, bytes, runes and characters in Go
+for more information.

+
+          
+          
+	        
+            
+          
+        
+