Quality Management:Quality manual/Work instructions/JavaScript coding standard
This document is not released - Draft version only
This coding standard is used for all JavaScript programming. That is, but not limited to, JavaScript and extensions to Dojo, YUI, jQuery and Prototype.
The scope of this document is to define coding standards related to the JavaScript language. Review and quality control is not covered herein. Please refer to Review procedure.
JavaScript
This document is under preparation, the following areas should be covered:
- PHP test page
- sourcefile/production file
- naming..
Validation
All released java scripts must be validated by JSLint.com or similar tools, However, the following exceptions are allowed: • It is not recommended to use the “ (??) Any exception shall be explained in the comments to the actual code line.
Furthermore, the script shall be run in Firefox and verified in the error console Firebug. tools, error console
File header
All source files must contain a file header with informations specified by the procedure for Control of Documents. An practical example may be found below:#Document History. Text to copy into the source file may be found here: Source file header.
Function names
All functions names starts with low-case.
Constructor
The variable name of variable containing a function reference must start upper-case.
<script type="text/javascript">
var Person = function(name){
this.name = name;
}
var eljefe = new Person ('Peter Stig Andersen');
print(eljefe.name);
</script>
This is to avoid programming errors where the lack of "new" would lead to use/modification of the global context.
Variable declaration
All variables must be declared prior to use.
<script type="text/javascript">
// a globally-scoped variable
var a=1;
// global scope
function one(){
a = 2;
alert(a);
}
</script>
and
<script type="text/javascript">
// a globally-scoped variable
var a=1;
// local scope
function one(){
var a = 2;
alert(a);
}
</script>
Provides different functions!
Don't use HTML comment within javascript
To day all browsers are able to handle the <script> tag, therefore there is no need for the construction used (before year 2000) to handle java script incompatible browsers. Furthermore, today some browsers eg. IE will hide java script enclosed by the HTML comments!
Therefore, never use this construction:
<script type="text/javascript">
<!--
// code here
//-->
</script>
Dojo
- Read more about Dojo and Declarative HTML5
References
To be reviewed:
References:
- Best Practices Java Script
- vs.dojo vs.yui (Performance)
- See all references here: References.
Document History
Version | Date | Author | Status | Purpose of update |
---|---|---|---|---|
1 | 23 Apr 2011 | PSA | Draft | New document |
2 | 25 Okt 2011 | PSA | Draft | Don't use HTML comments.. added. |