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Diffstat (limited to 'doc/codelab/wiki/wiki.html')
| -rw-r--r-- | doc/codelab/wiki/wiki.html | 49 |
1 files changed, 25 insertions, 24 deletions
diff --git a/doc/codelab/wiki/wiki.html b/doc/codelab/wiki/wiki.html index 91221bd616..634babd8b8 100644 --- a/doc/codelab/wiki/wiki.html +++ b/doc/codelab/wiki/wiki.html @@ -7,7 +7,7 @@ Covered in this codelab: <ul> <li>Creating a data structure with load and save methods</li> <li>Using the <code>http</code> package to build web applications -<li>Using the <code>old/template</code> package to process HTML templates</li> +<li>Using the <code>template</code> package to process HTML templates</li> <li>Using the <code>regexp</code> package to validate user input</li> <li>Using closures</li> </ul> @@ -366,27 +366,27 @@ This function will work fine, but all that hard-coded HTML is ugly. Of course, there is a better way. </p> -<h2>The <code>old/template</code> package</h2> +<h2>The <code>template</code> package</h2> <p> -The <code>old/template</code> package is part of the Go standard library. +The <code>template</code> package is part of the Go standard library. (A new template package is coming; this code lab will be updated soon.) We can -use <code>old/template</code> to keep the HTML in a separate file, allowing +use <code>template</code> to keep the HTML in a separate file, allowing us to change the layout of our edit page without modifying the underlying Go code. </p> <p> -First, we must add <code>old/template</code> to the list of imports: +First, we must add <code>template</code> to the list of imports: </p> <pre> import ( "http" "io/ioutil" - <b>"old/template"</b> "os" + <b>"template"</b> ) </pre> @@ -414,19 +414,21 @@ The function <code>template.ParseFile</code> will read the contents of </p> <p> -The method <code>t.Execute</code> replaces all occurrences of -<code>{Title}</code> and <code>{Body}</code> with the values of -<code>p.Title</code> and <code>p.Body</code>, and writes the resultant -HTML to the <code>http.ResponseWriter</code>. +The method <code>t.Execute</code> executes the template, writing the +generated HTML to the <code>http.ResponseWriter</code>. +The <code>.Title</code> and <code>.Body</code> dotted identifiers refer to +<code>p.Title</code> and <code>p.Body</code>. </p> <p> -Note that we've used <code>{Body|html}</code> in the above template. -The <code>|html</code> part asks the template engine to pass the value -<code>Body</code> through the <code>html</code> formatter before outputting it, -which escapes HTML characters (such as replacing <code>></code> with -<code>&gt;</code>). -This will prevent user data from corrupting the form HTML. +Template directives are enclosed in double curly braces. +The <code>printf "%s" .Body</code> instruction is a function call +that outputs <code>.Body</code> as a string instead of a stream of bytes, +the same as a call to <code>fmt.Printf</code>. +The <code>|html</code> part of each directive pipes the value through the +<code>html</code> formatter before outputting it, which escapes HTML +characters (such as replacing <code>></code> with <code>&gt;</code>), +preventing user data from corrupting the form HTML. </p> <p> @@ -572,10 +574,10 @@ our <code>*Template</code> values, keyed by <code>string</code> <p> Then we create an <code>init</code> function, which will be called before <code>main</code> at program initialization. The function -<code>template.MustParseFile</code> is a convenience wrapper around -<code>ParseFile</code> that does not return an error code; instead, it panics -if an error is encountered. A panic is appropriate here; if the templates can't -be loaded the only sensible thing to do is exit the program. +<code>template.Must</code> is a convenience wrapper that panics when passed a +non-nil <code>os.Error</code> value, and otherwise returns the +<code>*Template</code> unaltered. A panic is appropriate here; if the templates +can't be loaded the only sensible thing to do is exit the program. </p> <pre> @@ -618,10 +620,9 @@ Then we can create a global variable to store our validation regexp: <p> The function <code>regexp.MustCompile</code> will parse and compile the regular expression, and return a <code>regexp.Regexp</code>. -<code>MustCompile</code>, like <code>template.MustParseFile</code>, -is distinct from <code>Compile</code> in that it will panic if -the expression compilation fails, while <code>Compile</code> returns an -<code>os.Error</code> as a second parameter. +<code>MustCompile</code> is distinct from <code>Compile</code> in that it will +panic if the expression compilation fails, while <code>Compile</code> returns +an <code>os.Error</code> as a second parameter. </p> <p> |