Reserved words

The following list indicates words you must not use for ColdFusion variables, user-defined function names, or custom tag names. Although you can safely use some of these words in some situations, you can prevent errors by avoiding them entirely.

• Built-in function names, such as Now or Hash can be used as variable names except for the following functions:
  • ParameterExists       
  • PreserveSingleQuotes
  • QuotedValueList      
  • ValueList

• Scope names, such as Form or Session.
• Operators, such as NEQ or IS. For more information, see Operators and expressions.
• The following language elements are keywords in a script syntax:
  • for
  • default
  • switch
  • case
  • continue
  • import
  • finally
  • local (inside function declaration)
  • interface
  • pageencoding
  • return
  • try
  • catch
  • in
  • else  
  • if  
  • while    
  • do    
  • break
• The following elements are reserved in both script and tags:
  • function
  • true
  • false
  • final
  • abstract
  • null – can be used as variable names but not as User-Defined Function name.
• You cannot use cfimport  as a variable in a script synatx .
• You cannot use tag names as User-Defined Functions in both tags and script syntaxes.