caraxian.jazz v0.1.18

Jazz is a simple template engine built specifically for nodejs. This is a custom version of jazz with the template open and close characters change to « and ».

Usage

var jazz = require("caraxian.jazz");
var sys = require("sys");

var template = jazz.compile("my template source code «someVariable»");
template.eval({"someVariable": "lolmuffin"}, function(data) { sys.puts(data); });

This example would output the following:

my template source code lolmuffin

Syntax

Printing variables

«someVariable»

This works for any type of expression, so the following should also work:

«users.fred»
«"hello"»
«45»
«a eq b»

Filter functions

You can call filter functions like so:

«someFilter(arg1, arg2)»

Filter functions are statements, NOT expressions so they cannot be chained nor used in if/forelse/etc. tests. However, calls can be made on any type of expression -- e.g.

«math.sin(45)»

Implementing filter functions

Filter functions may block so rather than returning the value you want rendered as you might in other frameworks, jazz passes in a callback to your filter function that you then call to indicate that you have a result. e.g. here we simulate a blocking operation using setTimeout().

// sum.jazz

«sum(5, 10)»

// sum.js

var jazz = require("jazz");

var params = {
    sum: function(arg1, arg2, cb) {
        setTimeout(function() {
            cb((arg1 + arg2).toString());
        }, 2000);
    }
}
jazz.compile("sum.jazz").eval(params, function(output) { console.log(output); });

Note that even though the execution of the callback is delayed, this example still works.

Conditional Statements

You can check if a variable evaluates to a true value like so:

«if name»
    Hello, «name»
«end»

Else clauses are also supported:

«if name»
    Hello, «name»
«else»
    Hello, Captain Anonymous
«end»

As are else..if clauses:

«if firstName»
    Hello, «firstName»
«elif lastName»
    Hello, Mr. «lastName»
«else»
    Hello, Captain Anonymous
«end»

Limited logical expressions are also possible:

«if user.lastName and user.isVip»
    Hello, Mr. «user.lastName», my good man!
«end»

«if fred.tired or fred.bored»
    Fred: "Yawn!"
«end»

«if not awake»
    Zzz
«end»

eq & neq comparison operators are available for comparing two values:

«if config.feature eq "enabled"»
    Feature is enabled!
«end»

«if status neq "inactive"»
    Huzzah!
«end»

You can also group expressions using parentheses:

«if (a and b) or c»
    ...
«end»

Looping over an array

«foreach item in someArray»
    <p>«item»</p>
«end»

The value being iterated over can be any expression supporting an Array-like interface.

Looping over an object

«foreach pair in someObject»
    <p>«pair.key» = «pair.value»</p>
«end»

Synchronous functions

«if @blah('a')»
    <p>There were so many blahs in a</p>
«end»

The function is provided to the template the same way asynchronous functions are, just with a return instead of a cb.

Loop counters / index

«foreach pair in someObject»
    <p>Loop number (1 based): «__count»</p>
    <p>Index (0 based): «__index»</p>
    <p>«pair.key» = «pair.value»</p>
«end»

Looking into arrays/objects

    <p>«object['array'][0].cheese»</p>