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"

Tips

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.