Mercurial Hosting > luan
changeset 382:8557581740db
added tutorial
| author | Franklin Schmidt <fschmidt@gmail.com> |
|---|---|
| date | Wed, 22 Apr 2015 20:38:48 -0600 |
| parents | 83efd1e3685c |
| children | 4118eb51c816 |
| files | website/src/docs.html website/src/examples/hi.luan website/src/examples/hi2.luan website/src/examples/shell.luan website/src/manual.html website/src/tutorial.html.luan |
| diffstat | 6 files changed, 184 insertions(+), 27 deletions(-) [+] |
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--- a/website/src/docs.html Wed Apr 22 13:17:35 2015 -0600 +++ b/website/src/docs.html Wed Apr 22 20:38:48 2015 -0600 @@ -20,7 +20,8 @@ <big> <p> - <a href="pil.html">Programming in Lua</a><br> + <a href="tutorial.html">Tutorial</a><br> + <a href="pil.html">Programming in Lua (book)</a><br> <a href="manual.html">Reference Manual</a><br> <a href="diff.html">How Luan differs from Lua</a><br> </p>
--- /dev/null Thu Jan 01 00:00:00 1970 +0000 +++ b/website/src/examples/hi.luan Wed Apr 22 20:38:48 2015 -0600 @@ -0,0 +1,13 @@ +local Io = require "luan:Io" +local Http = require "luan:web/Http" + +function service() + Io.stdout = Http.response.text_writer() + %> + <html> + <body> + Hello World + </body> + </html> + <% +end
--- /dev/null Thu Jan 01 00:00:00 1970 +0000 +++ b/website/src/examples/hi2.luan Wed Apr 22 20:38:48 2015 -0600 @@ -0,0 +1,38 @@ +local Io = require "luan:Io" +local Http = require "luan:web/Http" + +local function form() +%> +<html> + <body> + <h1>Hello</h1> + <form> + What is you name? + <input name="name"> + <input type=submit> + </form> + </body> +</html> +<% +end + +local function hello() +%> +<html> + <body> + <h1>Hello</h1> + <p>Hi <%= name %>!</p> + </body> +</html> +<% +end + +function service() + Io.stdout = Http.response.text_writer() + name = Http.request.parameters.name + if name == nil then + form() + else + hello() + end +end
--- /dev/null Thu Jan 01 00:00:00 1970 +0000 +++ b/website/src/examples/shell.luan Wed Apr 22 20:38:48 2015 -0600 @@ -0,0 +1,1 @@ +return require "luan:web/shell"
--- a/website/src/manual.html Wed Apr 22 13:17:35 2015 -0600 +++ b/website/src/manual.html Wed Apr 22 20:38:48 2015 -0600 @@ -299,10 +299,9 @@ You can emulate how Luan queries a metamethod for an object <tt>obj</tt> with the following code: -<tt><pre> +<p><tt><pre> raw_get(get_metatable(obj) or {}, "__" .. event_name) - -</pre></tt> +</pre></tt></p> <p> Here are the events: @@ -529,12 +528,12 @@ and cannot be used as names: -<pre> +<p><pre> and break do else elseif end false for function goto if in local nil not or repeat return then true until while -</pre> +</pre></p> <p> Luan is a case-sensitive language: @@ -545,14 +544,13 @@ <p> The following strings denote other tokens: -<pre> +<p><pre> + - * / % ^ # & ~ | << >> // == ~= <= >= < > = ( ) { } [ ] :: ; : , . .. ... - -</pre> +</pre></p> <p> <i>Literal strings</i> @@ -631,7 +629,7 @@ As an example the five literal strings below denote the same string: -<pre> +<p><pre> a = 'alo\n123"' a = "alo\n123\"" a = '\97lo\10\04923"' @@ -640,8 +638,7 @@ a = [==[ alo 123"]==] - -</pre> +</pre></p> <p> A <i>numerical constant</i> (or <i>numeral</i>) @@ -658,17 +655,17 @@ otherwise it denotes an integer. Examples of valid integer constants are -<pre> +<p><pre> 3 345 0xff 0xBEBADA - -</pre><p> +</pre></p> + +<p> Examples of valid float constants are -<pre> +<p><pre> 3.0 3.1416 314.16e-2 0.31416E1 34e1 0x0.1E 0xA23p-4 0X1.921FB54442D18P+1 - -</pre> +</pre></p> <p> A <i>comment</i> starts with a double hyphen (<tt>--</tt>) @@ -697,10 +694,11 @@ (or a function's formal parameter, which is a particular kind of local variable): -<pre> +<p><pre> var ::= Name - -</pre><p> +</pre></p> + +<p> Name denotes identifiers, as defined in <a href="#3.1">§3.1</a>. @@ -719,10 +717,11 @@ <p> Square brackets are used to index a table: -<pre> +<p><pre> var ::= prefixexp ‘<b>[</b>’ exp ‘<b>]</b>’ - -</pre><p> +</pre></p> + +<p> The meaning of accesses to table fields can be changed via metatables. An access to an indexed variable <tt>t[i]</tt> is equivalent to a call <tt>gettable_event(t,i)</tt>. @@ -736,10 +735,9 @@ The syntax <tt>var.Name</tt> is just syntactic sugar for <tt>var["Name"]</tt>: -<pre> +<p><pre> var ::= prefixexp ‘<b>.</b>’ Name - -</pre> +</pre></p> <p> An access to a global variable <tt>x</tt>
--- /dev/null Thu Jan 01 00:00:00 1970 +0000 +++ b/website/src/tutorial.html.luan Wed Apr 22 20:38:48 2015 -0600 @@ -0,0 +1,106 @@ +local Io = require "luan:Io" +local Html = require "luan:Html" +local Http = require "luan:web/Http" + +function service() + Io.stdout = Http.response.text_writer() + Io.stdout = Http.response.text_writer() + Html.simply_html_page{ + head = function() %> + <title>Luan Tutorial</title> +<% end; + body = function() %> + +<div container> +<div><small><a href="/">Luan</a></small></div> +<h1 margin-bottom="1em">Luan Tutorial</h1> + + +<p>Create a file <b>hello.luan</b> containing:</p> + +<p><tt><pre><%=Html.encode[[ + %> + Hello World + <% +]]%></pre></tt></p> + +<p>To run this, type <b>luan file:hello</b> on the command line. This should print <b>Hello World</b>.</p> + +<p>The syntax here is based on <a href="http://en.wikipedia.org/wiki/JavaServer_Pages">JSP</a>. Let's change it a little:</p> + +<p><tt><pre><%=Html.encode[[ + name = "Bob" + %> + Hello <%= name %> + <% +]]%></pre></tt></p> + +<p>This should print <b>Hello Bob</b>. Now let's try a more conventional approach:</p> + +<p><tt><pre> + local Io = require "luan:Io" + local print = Io.print + + print("Hello World") +</pre></tt></p> + +<p>In Luan, a function call with one string argument doesn't require parenthesis, so <b>print("Hello World")</b> is the same as <b>print "Hello World"</b> and <b>require "luan:Io"</b> is the same as <b>require("luan:Io")</b>. Both <b>require</b> and <b>print</b> are functions.</p> + +<p>The <b>require</b> function takes a <a href="http://en.wikipedia.org/wiki/Uniform_resource_identifier">URI</a> as an argument. Examples of URIs are "<b>luan:Io</b>" and "<b>file:hello</b>". <b>require</b> is used to import a module, which is returned from the <b>require</b> function call. In the case above, we assign the module to the local variable <b>Io</b>. The function <b>print</b> is a member of this module. We could have done <b>Io.print("Hello World")</b> but instead we chose to assign <b>print</b> to a local variable and use that to call the function.</p> + +<p>Luan starts with only two defined functions: <b>require</b> and <b>java</b>. You will use <b>require</b> to import whatever you need. This is a little more work, but makes it clear in each file where each function comes from.</p> + +<p>Let's a make fancier version:</p> + +<p><tt><pre> + local Io = require "luan:Io" + local print = Io.print + + function hell(name) + print("Hello "..name) + end + + hello("Bob") +</pre></tt></p> + +<p>The <b>..</b> operator does concatenation. This will print <b>Hello Bob</b>.</p> + +<p>Now let's make a web page. First we need a directory for our website. So create a directory <b>site</b>. In this directory, create a file <b>hi.luan</b> containing: + +<p><tt><pre><%=Html.encode[[ + local Io = require "luan:Io" + local Http = require "luan:web/Http" + + function service() + Io.stdout = Http.response.text_writer() + %> + <html> + <body> + Hello World + </body> + </html> + <% + end +]]%></pre></tt></p> + +<p>Now go back to the parent directory and do <b>luan luan:web/serve file:site</b>. This will run the Luan web server on port 8080. Try going to <a href="http://localhost:8080/">http://localhost:8080/</a>. You should see the directory. If you click on <b>hi.luan</b> you will see the source. But if you remove the <b>.luan</b> and just go to <a href="http://localhost:8080/hi">http://localhost:8080/hi</a> then you will run the program which will generate the web page.</p> + +<p>The Luan webserver looks for function named <b>service</b> in the file and calls it to generate the page. Code of the form <b><%=Html.encode[[%>...<%]]%></b> writes its output to <b>Io.stdout</b> which by default is the standard output of the command line. So in <b>service</b> one usually starts by setting <b>Io.stdout</b> to a <tt>text_writer</tt> which writes its output to the HTTP response (to the web browser).</p> + +<p>You can find this example and others in the <a href="examples">examples directory</a>. Take a look at <a href="examples/hi2.luan">hi2.luan</a> next. Remember to remove the <b>.luan</b> from the URL to run the code. And by the way, you can see the source for this page at <a href="tutorial.html.luan">tutorial.html.luan</a>.</p> + +<p>So now you have built your website and you want publish it to the web. If you have your own domain, create a CNAME record for it pointing to <b>s1.luanhost.com</b>. If you don't have a domain, just use a domain like <b>bob.s1.luanhost.com</b> (anything of the form <b>*.s1.luanhost.com</b>). Assuming your directory is <b>site</b> and you will use the password <b>secret</b>, do the following from the command line: + +<p><tt><pre> + luan luan:host/push bob.s1.luanhost.com secret site +</pre></tt></p> + +<p>The form is <b>luan luan:host/push domain password directory</b>. If you change your site, just run this again and your site will be updated. To delete your site, do <b>luan luan:host/delete domain password</b>.</p> + +<p>Hopefully this short tutorial gave you an idea of how to use Luan to make a website.</p> + +</div> + +<% end; + } +end