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Merge vector layers.

Name	Type	Identifier	Description	Constraints
Input
Layers	shapes list, input	INPUT	Output will inherit shape type and table structure from the first layer in this list.
Output
Merged Layer	shapes, output	MERGED
Options
Add Source Information	boolean	SRCINFO	Adds a field with the name of the original input data set.	Default: 1
Match Fields by Name	boolean	MATCH		Default: 1
Delete	boolean	DELETE	Deletes each input data set immediately after it has been merged, thus saving memory resources.	Default: 0