Add Walk

2019-06-08 11:20:00 -07:00 · 2019-06-08 11:20:00 -07:00 · 1be2c1c910
commit 1be2c1c910
parent ee8c401ac3
4 changed files with 89 additions and 17 deletions
--- a/examples/directories/directories.go
+++ b/examples/directories/directories.go
@ -7,6 +7,7 @@ import (
 	"fmt"
 	"io/ioutil"
 	"os"
+	"path/filepath"
 )

 func check(e error) {
@ -53,7 +54,7 @@ func main() {

 	fmt.Println("Listing subdir/parent")
 	for _, entry := range c {
-		fmt.Println(entry.Name(), entry.IsDir())
+		fmt.Println(" ", entry.Name(), entry.IsDir())
 	}

 	// `Chdir` lets us change the current working directory,
@ -68,10 +69,27 @@ func main() {

 	fmt.Println("Listing subdir/parent/child")
 	for _, entry := range c {
-		fmt.Println(entry.Name(), entry.IsDir())
+		fmt.Println(" ", entry.Name(), entry.IsDir())
 	}

 	// `cd` back to where we started.
 	err = os.Chdir("../../..")
 	check(err)
+
+	// We can also visit a directory *recursively*,
+	// including all its sub-directories. `Walk` accepts
+	// a callback function to handle every file or
+	// directory visited.
+	fmt.Println("Visiting subdir")
+	err = filepath.Walk("subdir", visit)
+}
+
+// visit is called for every file or directory found
+// recursively by `filepath.Walk`.
+func visit(p string, info os.FileInfo, err error) error {
+	if err != nil {
+		return err
+	}
+	fmt.Println(" ", p, info.IsDir())
+	return nil
 }
--- a/examples/directories/directories.hash
+++ b/examples/directories/directories.hash
@ -1,2 +1,2 @@
-7b2eed223a00c8a84df582bd254a642c7a57dd9b
-UnjBL6NmR8-
+57a8f629f040270c15a0375be4424b392edf3c95
+LI7ty_KDozd
--- a/examples/directories/directories.sh
+++ b/examples/directories/directories.sh
@ -1,7 +1,15 @@
 $ go run directories.go
 Listing subdir/parent
-child true
-file2 false
-file3 false
+  child true
+  file2 false
+  file3 false
 Listing subdir/parent/child
-file4 false
+  file4 false
+Visiting subdir
+  subdir true
+  subdir/file1 false
+  subdir/parent true
+  subdir/parent/child true
+  subdir/parent/child/file4 false
+  subdir/parent/file2 false
+  subdir/parent/file3 false
--- a/public/directories
+++ b/public/directories
@ -28,7 +28,7 @@
            
          </td>
          <td class="code leading">
-            <a href="http://play.golang.org/p/UnjBL6NmR8-">
+            <a href="http://play.golang.org/p/LI7ty_KDozd">
              <img title="Run code" class="run" src="data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAABAAAAAPCAYAAADtc08vAAAABGdBTUEAANbY1E9YMgAAABl0RVh0U29mdHdhcmUAQWRvYmUgSW1hZ2VSZWFkeXHJZTwAAAJ1SURBVCjPY/j//z8DMu7o6GAAgpQgD9tLqcmJH4KDg14aaik/MtdXe2ZjY6OCrh6Fs2jRYmZ9Pd05M9uL/u9dPfU/CLS0dfxvKIz/X5Dg/z8pKdkGqwGpqakMUdExDHJSYqt37tjxf+qUSf9rc2P+79298/+RA3v+H1zV///o6r7/DrbWFQkJiQwxMTGoBjAxMTpKiQmuqMuP/f/xw/v/J0+f/W9tbvTfxVLn/8rJVf+v757z/96hRf8TQtxuCQmLMjk4OKAawMfDVWVvrvd85eTq/7tXTP6/e/XM/22lif9LCnL+b13Q/v/Kzln/L++c/X/7/Jb/VpYWuZFRUagGAAErEBtlxvi+vn944f9L26cDNcz6v21R9/8zm6aC2SBDbu+f/78kK+4/L79AO7oBYCAqxD/57JZp/y/tmPX/wrYZ/6+CbAayD6zs/78daBjIgPayFJAGG6wGAIFAcpjH/dv7F4ANABuya/b/Od3l/ye2V/+/tnv2/7ldxSANmrgMYGBhZg7fuagD7GyYIeeBrrqwdRrQgLn/l02sBGkwwWkAEAjV5EZ/vQV0LswAGAYZsLC3DKTBAJ8BzCkRni/uHFyIYcAtoNc6ypL/ANVIohigrKwMxqqqqgxMzKzM6VHeL+6iGQAKzDtAV5XlJv3n5uFLRTHgzZs3YPzz50+GwqJiPitD9Y8Pjy4BB+CNvfP+3wUmIpAhhckhr3X19LodHZ28UQxQU1MDYw0NDQYBAQEeoBOTK7JjP2xf3Pt/bkfB/4KkoDcKMmIL5OXlFerq6hhu3rzJgC8MwMDYxGSfm5vbVn9/f0cgVxAkpqioyFBfX49iAACbTAK+xT3CzgAAAABJRU5ErkJggg==" />
            </a>
            <div class="highlight"><pre><span class="kn">package</span> <span class="nx">main</span>
@ -47,6 +47,7 @@
    <span class="s">&quot;fmt&quot;</span>
    <span class="s">&quot;io/ioutil&quot;</span>
    <span class="s">&quot;os&quot;</span>
+    <span class="s">&quot;path/filepath&quot;</span>
 <span class="p">)</span>
 </pre></div>

@ -143,7 +144,7 @@ will delete a whole directory tree (similarly to
        <tr>
          <td class="docs">
            <p>We can create a hierarchy of directories, including
-parents wiht <code>MkdirAll</code>. This is similar to the
+parents with <code>MkdirAll</code>. This is similar to the
 command-line <code>mkdir -p</code>.</p>

          </td>
@ -193,7 +194,7 @@ slice of <code>os.FileInfo</code> objects.</p>
            
            <div class="highlight"><pre>    <span class="nx">fmt</span><span class="p">.</span><span class="nx">Println</span><span class="p">(</span><span class="s">&quot;Listing subdir/parent&quot;</span><span class="p">)</span>
    <span class="k">for</span> <span class="nx">_</span><span class="p">,</span> <span class="nx">entry</span> <span class="o">:=</span> <span class="k">range</span> <span class="nx">c</span> <span class="p">{</span>
-        <span class="nx">fmt</span><span class="p">.</span><span class="nx">Println</span><span class="p">(</span><span class="nx">entry</span><span class="p">.</span><span class="nx">Name</span><span class="p">(),</span> <span class="nx">entry</span><span class="p">.</span><span class="nx">IsDir</span><span class="p">())</span>
+        <span class="nx">fmt</span><span class="p">.</span><span class="nx">Println</span><span class="p">(</span><span class="s">&quot; &quot;</span><span class="p">,</span> <span class="nx">entry</span><span class="p">.</span><span class="nx">Name</span><span class="p">(),</span> <span class="nx">entry</span><span class="p">.</span><span class="nx">IsDir</span><span class="p">())</span>
    <span class="p">}</span>
 </pre></div>

@ -238,7 +239,7 @@ when listing the <em>current</em> directory.</p>
            
            <div class="highlight"><pre>    <span class="nx">fmt</span><span class="p">.</span><span class="nx">Println</span><span class="p">(</span><span class="s">&quot;Listing subdir/parent/child&quot;</span><span class="p">)</span>
    <span class="k">for</span> <span class="nx">_</span><span class="p">,</span> <span class="nx">entry</span> <span class="o">:=</span> <span class="k">range</span> <span class="nx">c</span> <span class="p">{</span>
-        <span class="nx">fmt</span><span class="p">.</span><span class="nx">Println</span><span class="p">(</span><span class="nx">entry</span><span class="p">.</span><span class="nx">Name</span><span class="p">(),</span> <span class="nx">entry</span><span class="p">.</span><span class="nx">IsDir</span><span class="p">())</span>
+        <span class="nx">fmt</span><span class="p">.</span><span class="nx">Println</span><span class="p">(</span><span class="s">&quot; &quot;</span><span class="p">,</span> <span class="nx">entry</span><span class="p">.</span><span class="nx">Name</span><span class="p">(),</span> <span class="nx">entry</span><span class="p">.</span><span class="nx">IsDir</span><span class="p">())</span>
    <span class="p">}</span>
 </pre></div>

@ -250,10 +251,47 @@ when listing the <em>current</em> directory.</p>
            <p><code>cd</code> back to where we started.</p>

          </td>
-          <td class="code">
+          <td class="code leading">
            
            <div class="highlight"><pre>    <span class="nx">err</span> <span class="p">=</span> <span class="nx">os</span><span class="p">.</span><span class="nx">Chdir</span><span class="p">(</span><span class="s">&quot;../../..&quot;</span><span class="p">)</span>
    <span class="nx">check</span><span class="p">(</span><span class="nx">err</span><span class="p">)</span>
+</pre></div>
+
+          </td>
+        </tr>
+        
+        <tr>
+          <td class="docs">
+            <p>We can also visit a directory <em>recursively</em>,
+including all its sub-directories. <code>Walk</code> accepts
+a callback function to handle every file or
+directory visited.</p>
+
+          </td>
+          <td class="code leading">
+            
+            <div class="highlight"><pre>    <span class="nx">fmt</span><span class="p">.</span><span class="nx">Println</span><span class="p">(</span><span class="s">&quot;Visiting subdir&quot;</span><span class="p">)</span>
+    <span class="nx">err</span> <span class="p">=</span> <span class="nx">filepath</span><span class="p">.</span><span class="nx">Walk</span><span class="p">(</span><span class="s">&quot;subdir&quot;</span><span class="p">,</span> <span class="nx">visit</span><span class="p">)</span>
+<span class="p">}</span>
+</pre></div>
+
+          </td>
+        </tr>
+        
+        <tr>
+          <td class="docs">
+            <p>visit is called for every file or directory found
+recursively by <code>filepath.Walk</code>.</p>
+
+          </td>
+          <td class="code">
+            
+            <div class="highlight"><pre><span class="kd">func</span> <span class="nx">visit</span><span class="p">(</span><span class="nx">p</span> <span class="kt">string</span><span class="p">,</span> <span class="nx">info</span> <span class="nx">os</span><span class="p">.</span><span class="nx">FileInfo</span><span class="p">,</span> <span class="nx">err</span> <span class="kt">error</span><span class="p">)</span> <span class="kt">error</span> <span class="p">{</span>
+    <span class="k">if</span> <span class="nx">err</span> <span class="o">!=</span> <span class="kc">nil</span> <span class="p">{</span>
+        <span class="k">return</span> <span class="nx">err</span>
+    <span class="p">}</span>
+    <span class="nx">fmt</span><span class="p">.</span><span class="nx">Println</span><span class="p">(</span><span class="s">&quot; &quot;</span><span class="p">,</span> <span class="nx">p</span><span class="p">,</span> <span class="nx">info</span><span class="p">.</span><span class="nx">IsDir</span><span class="p">())</span>
+    <span class="k">return</span> <span class="kc">nil</span>
 <span class="p">}</span>
 </pre></div>

@ -272,11 +310,19 @@ when listing the <em>current</em> directory.</p>
            
            <div class="highlight"><pre><span class="gp">$</span> go run directories.go
 <span class="go">Listing subdir/parent</span>
-<span class="go">child true</span>
-<span class="go">file2 false</span>
-<span class="go">file3 false</span>
+<span class="go">  child true</span>
+<span class="go">  file2 false</span>
+<span class="go">  file3 false</span>
 <span class="go">Listing subdir/parent/child</span>
-<span class="go">file4 false</span>
+<span class="go">  file4 false</span>
+<span class="go">Visiting subdir</span>
+<span class="go">  subdir true</span>
+<span class="go">  subdir/file1 false</span>
+<span class="go">  subdir/parent true</span>
+<span class="go">  subdir/parent/child true</span>
+<span class="go">  subdir/parent/child/file4 false</span>
+<span class="go">  subdir/parent/file2 false</span>
+<span class="go">  subdir/parent/file3 false</span>
 </pre></div>

          </td>