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Syntax

There are two ways to write ColdFusion (CFML) code: in tags or in script syntax. Modern CFML will dictate that your view or presentation layers will utilize the tag syntax in cfm files and the model or business layers will be all done in script syntax in cfc files. (MVC comes later)

Syntax Files

CFML includes a set of instructions you use in pages (.cfm) or components (classes -cfc). You will write one or more instructions in a file (.cfm,.cfc) then run the file through a CFML engine or Command Line Interpreter like CommandBox.

  • cfm - ColdFusion markup file, tag syntax is the default
  • cfc - ColdFusion Component file (Class or Object), script syntax is the default.

Implicit Behavior

CFML also gives you a pre-set of defined tags and functions available to you in any type of file you write your code in. These tags and functions allows you to extend the typical language constructs with many modern capabilities from database interaction to PDF generation.

{% hint style="success" %} Tip: Please note that the CFML built-in functions are also first-class functions so they can be passed around as arguments to other functions or closures. {% endhint %}

Exploring Behavior

Three CFML instructions we will use in this section are cfset, cfoutput, and cfdump. cfset is used to create a variable and assign it a value. Also cfset is used to call methods. cfoutput displays a variable's value. cfdump is used to display the contents of simple and complex variables, objects, components, user-defined functions, and other elements.

We might have a file named myprogram.cfm and Sample.cfc like this:

Tag Syntax

myprogram.cfm

{% code-tabs %} {% code-tabs-item title="myprogram.cfm" %}

<cfset s = new Sample()>
<cfoutput>#s.hello()#</cfoutput>

{% endcode-tabs-item %} {% endcode-tabs %}

Script Syntax

myprogram.cfm

{% code-tabs %} {% code-tabs-item title="myprogram.cfm" %}

<cfscript>
    s = new Sample();
    writeOutput( s.hello() );
</cfscript>

{% endcode-tabs-item %} {% endcode-tabs %}

Sample.cfc

{% code-tabs %} {% code-tabs-item title="Sample.cfc" %}

component{

    function hello(){
       return "Hello, World!";
    }

}

{% endcode-tabs-item %} {% endcode-tabs %}

Please note that no types and not even any visibility scopes you might be used to are present. ColdFusion can infer variable types (Lucee) as well. However, please note that you can fully leverage types if you like:

{% code-tabs %} {% code-tabs-item title="Sample.cfc" %}

component{

    public string function hello(){
       return "Hello, World!";
    }

}

{% endcode-tabs-item %} {% endcode-tabs %}

{% hint style="success" %} By default the return type of every function and/or argument is any. Thus, it can be determined at runtime as a dynamic variable. {% endhint %}

Semi-Colons

Please note that semi-colons are used to demarcate line endings in CFML ;. However, the Lucee Server engine can treat semi-colons as optional, while Adobe ColdFusion does not. Be worrisome about it, we would recommend you always use them to remain compatible between engines. Also note the CommandBox REPL does NOT require semi-colons.

Tags In Script

Both Lucee and Adobe ColdFusion 11+ will allow you to write your CFML tags in script syntax. You basically eliminate the starting < and ending > enclosures and create context by using the { and } mustaches.

cfhttp(method="GET", charset="utf-8", url="https://www.google.com/", result="result") {
    cfhttpparam(name="q", type="formfield", value="cfml");
}

Polyglot References

As we now live in a world of polyglot developers, we have added a few references below to other languages so you can see the differences and similarities between CFML and other major languages in usage today. Please note that this section is merely academic and to help developer from other language backgrounds to understand the intricacies of the ColdFusion (CFML) syntax.

PHP Syntax

myprogram.php

{% code-tabs %} {% code-tabs-item title="myprogram.php" %}

<?php
    require("Sample.php");
    $s = new Sample();
    echo $s->hello();
?>

{% endcode-tabs-item %} {% endcode-tabs %}

Sample.php

{% code-tabs %} {% code-tabs-item title="Sample.php" %}

<?php
class Sample
{
    public function hello() {
        return "Hello, World!";
    }
}
?>

{% endcode-tabs-item %} {% endcode-tabs %}

Ruby Syntax

myprogram.rb

{% code-tabs %} {% code-tabs-item title="myprogram.rb" %}

class Sample
    def hello
        "Hello, World!"
    end
end

s = Sample.new
puts s.hello

{% endcode-tabs-item %} {% endcode-tabs %}

Java Syntax

MyProgram.java

{% code-tabs %} {% code-tabs-item title="MyProgram.java" %}

public class MyProgram {

    public String hello(){
        return "Hello, world!";
    }

    public static void main(String[] args) {
        System.out.println( new MyProgram().hello() );
    }

}

{% endcode-tabs-item %} {% endcode-tabs %}

Coding Standards

At Ortus Solutions we have developed a set of development standards for many languages. You can find our ColdFusion standards here: https://github.com/Ortus-Solutions/coding-standards/blob/master/coldfusion.md