Syntax
Script or Tags? Choose wisely!
There are two ways to write 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 all be done in script syntax in cfc files. (MVC comes later). There are no differences in functionality between them; it's pure syntax.CFML includes a set of instructions you use on 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 and used for viewscfc- The default is the ColdFusion Component file (Class or Object), script syntax.
CFML also gives you a pre-set of defined tags and functions available to you in any file you write your code in. These tags and functions allow you to extend the typical language constructs with many modern capabilities, from database interaction to PDF generation. They are basically automatic imports.
Tip: Please note that the CFML built-in functions are also first-class functions so that they can be passed around as arguments to other functions or closures or saved as variables.
Three CFML instructions we will use in this section are
cfset, cfoutput, and cfdump.cfsetis used to create a variable and assign it a value.cfoutputdisplays a variable's value to the output stream.cfdumpis used to display the contents of simple and complex variables, objects, components, user-defined functions, and other elements to the output stream.
We might have a file named myprogram.cfm and Sample.cfc like this:
myprogram.cfm
<cfset s = new Sample()>
<cfoutput>#s.hello()#</cfoutput>
myprogram.cfm
<cfscript>
s = new Sample();
writeOutput( s.hello() );
</cfscript>
Tip: Please note that if you want to write in script in a tag-based file, you must use an opening and closing
<cfscript> tag.Sample.cfc
component{
function hello(){
return "Hello, World!";
}
}
Please note that no types and not even any visibility scopes you might be used to are present. CFML can also infer variable types on more distinct variables like dates, booleans, or numbers. However, please note that you can fully leverage types if you like:
Sample.cfc
component{
public string function hello(){
return "Hello, World!";
}
}
By default, the return type of every function and/or argument is any. Thus, it can be determined at runtime as a dynamic variable.
Please note that semi-colons are used to demarcate line endings in CFML
;. However, the Lucee Server engine and Adobe ColdFusion 2018+ treat semi-colons as optional, while Adobe ColdFusion 2016 or below does not. Also, note the CommandBox REPL does NOT require semi-colons.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 a block 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");
}
As we now live in a world of polyglot developers, we have added references below to other languages to 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 developers from other language backgrounds to understand the intricacies of the ColdFusion (CFML) syntax.
myprogram.php
<?php
require("Sample.php");
$s = new Sample();
echo $s->hello();
?>
Sample.php
<?php
class Sample
{
public function hello() {
return "Hello, World!";
}
}
?>
myprogram.rb
class Sample
def hello
"Hello, World!"
end
end
s = Sample.new
puts s.hello
MyProgram.java
public class MyProgram {
public String hello(){
return "Hello, world!";
}
public static void main(String[] args) {
System.out.println( new MyProgram().hello() );
}
}
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.
Last modified 2mo ago