JavaScript Optimizer - Extensions Syntax

The optimizer's syntax is based on C/C++ preprocessor. Here are all allowed directives:

Syntax	Description	Sample
#define [name]	The define directive marks the identifier [name] as existing. Marking an indentifier as existing is used to include JavaScript code fragments conditionally, based on existance/non-existance of given identifier (using #ifdef and #ifndef directives).	#define GENERATE_IE_CODE ... #ifdef GENERATE_IE_CODE // the code in this block // will be included #else // this code will not be included #endif
#define [name] [value]	This version of the define directive servers two purposes: it marks the identifier [name] as existing and it also will replace all occurrences of text [name] with [value] in all lines of the code following this define directive	#define SCRIPT_VERSION 5.0 BETA ... alert ("Script version is SCRIPT_VERSION"); // the above line will display: // Script version is 5.0 BETA
#undef [name]	Marks the identifier [name] as non-existing (reverses the action of the corresponding #define directive).	#define INSERT_DEBUG_CODE ... #ifdef INSERT_DEBUG_CODE // this code will be inserted #endif ... #undef INSERT_DEBUG_CODE #ifdef INSERT_DEBUG_CODE // this code will NOT be inserted #endif
#allundef	Marks all previously defined identifiers as non-existing.	#define INSERT_DEBUG_CODE ... #ifdef INSERT_DEBUG_CODE // this code will be inserted #endif ... #allundef #ifdef INSERT_DEBUG_CODE // this code will NOT be inserted #endif
#ifdef [name] [code A] #endif or #ifdef [name] [code A] #else [code B] #endif	Conditionally includes code. In case that an identifier named [name] is existing, [code A] will be included in the optimized version of the code. If using the second variant (with the #else directive), [code A] will be included if [name] exists; otherwise [code B] will be included. Please note that each #ifdef directive must be matched by a closing #endif directive. You can use an #ifdef directive inside other #ifdef directives (thus forming a complex AND condition).	#define INSERT_DEBUG_CODE ... #ifdef INSERT_DEBUG_CODE // this code will be inserted #ifdef ABC // this code will NOT be inserted // since ABC is not defined // and we'd need both ABC // and INSERT_DEBUG_CODE here #endif #endif ... #ifdef INSERT_DEBUG_CODE // this code will also be inserted #else // this code will NOT be inserted #endif
#ifndef [name] [code A] #endif or #ifndef [name] [code A] #else [code B] #endif	Conditionally includes code. In case that an identifier named [name] does NOT exist, [code A] will be included in the optimized version of the code. If using the second variant (with the #else directive), [code A] will be included if [name] DOES NOT exists; otherwise [code B] will be included. Please note that each #ifndef directive must be matched by a closing #endif directive. You can use an #ifndef directive inside other #ifdef or #ifndef directives.	#define INSERT_DEBUG_CODE ... #ifndef ABC // this code will be inserted #endif ... #ifndef INSERT_DEBUG_CODE // this code will NOT be inserted #endif ... #ifndef INSERT_DEBUG_CODE // this code will NOT be inserted either #else // this code will be inserted #endif
#include "[file]"	Includes the contents of file found at location specified by [file]. WARNING: This is not supported in the online version.	#include "abc.js"

• By adding the #define [name] [value] directive for frequently used function and variable names, you can further optimize the code. E.g. if you have two frequently used functions: AddHighlightToItem and RemoveHighlightFromItem, you can define them as: #define f1 AddHighlightToItem and #define f2 RemoveHighlightFromItem. Now, every time these names appear in your code you save 16 or 21 bytes.
• Conditionally included code can be very useful if you want to keep your debug code always available on demand; or - generally - if, based on your preferences, you decide to create a few versions of JavaScript code.