UnigineEditor
Interface Overview
Assets Workflow
Settings and Preferences
Working With Projects
Adjusting Node Parameters
Setting Up Materials
Setting Up Properties
Lighting
Landscape Tool
Sandworm (Experimental)
Using Editor Tools for Specific Tasks
Extending Editor Functionality
Programming
Fundamentals
Setting Up Development Environment
Usage Examples
C++
C#
UUSL (Unified UNIGINE Shader Language)
File Formats
Rebuilding the Engine Tools
GUI
Double Precision Coordinates
API
Containers
Common Functionality
Controls-Related Classes
Engine-Related Classes
Filesystem Functionality
GUI-Related Classes
Math Functionality
Node-Related Classes
Objects-Related Classes
Networking Functionality
Pathfinding-Related Classes
Physics-Related Classes
Plugins-Related Classes
IG Plugin
CIGIConnector Plugin
Rendering-Related Classes

Foreachkey

Warning
The scope of applications for UnigineScript is limited to implementing materials-related logic (material expressions, scriptable materials, brush materials). Do not use UnigineScript as a language for application logic, please consider C#/C++ instead, as these APIs are the preferred ones. Availability of new Engine features in UnigineScipt (beyond its scope of applications) is not guaranteed, as the current level of support assumes only fixing critical issues.

The foreachkey construct provides another way to iterate over vectors and maps. It is used to execute some code for each index or key in a given container.

Syntax

Source code (UnigineScript)
foreachkey(key_variable; map; loop_increment) {
	// some_code;
 }

Parts

  • key_variable is the current key (or index). The internal container cursor is moved to point at the next key-value pair (or indexed item).
  • The type of key_variable doesn't matter.
  • loop_increment is executed at the end of each iteration. It is optional.

Examples

  • Source code (UnigineScript)
    int map[] = ( "begin" : "flower", "middle" : "fruit", "end" : "tree" );
    foreachkey(int i; map) {
    	log.message("%s\t=>\t%s\n",i,map[i]);
    }
    The result is:
    Output
    begin   =>      flower
    end     =>      tree
    middle  =>      fruit
  • Source code (UnigineScript)
    int map[] = ( "begin" : "flower", "middle" : "fruit", "end" : "tree" );
    foreachkey(int i, j = 0; map; j++) {
    	log.message("%d: %s\t=>\t%s\n",j,i,map[i]);
    }
    The result is:
    Output
    0: begin   =>      flower
    1: end     =>      tree
    2: middle  =>      fruit
Notice
Before the execution keys are sorted in the ascending order.

Modifications of keys inside the foreachkey block do not affect the map, however, values can be modified directly.

Source code (UnigineScript)
int map[] = ( "begin" : "flower", "middle" : "fruit", "end" : "tree" );
foreachkey(int i; map) {
	i = "first";	// it doesn't affect the map
	map[i] = -9.6;	// it's ok, map is changed
}

Nesting foreachkey#

In case foreachkey structure is called within another foreachkey structure, for each block a copy of the map should be stored. (Such approach allows for higher performance.)

Source code (UnigineScript)
int map[] = ( "1" : "head", "2" : "foot" );

int copy[];
copy.copy(map);

foreachkey(int i; map) {
	foreachkey(int j; copy)	// foreachkey(int j; map) will generate an error
	{
		log.message("%s\t->\t%s\t%s\t->\t%s\n",i,map[i],j,map[j]);
	}
}
The output of the example is:
Output
1	->	head	1	->	head
1	->	head    2	->	foot
2	->	foot	1	->	head
2	->	foot	2	->	foot
Last update: 2017-07-03