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monitor_changes(+Vars, +Templates, +Prio, +CondList, +AttrMod, -ChangeStream)

Monitor variables for modifications

Vars: A list containing variables
Templates: A list of terms corresponding to the variables
Prio: Priority for the monitoring demons
CondList: Suspension list spec
AttrMod: Suspension list attribute module
ChangeStream: A lazy list of lists of changes

Description

Like monitor_changes_arr/5, but (instead of array indices) the ChangeStream contains the elements of the Templates-list that correspond to the modified variables, thus allowing arbitrary information to be conveyed to the code that processes the changes.

    [eclipse 10]: X1::1..9, X2::1..8,
	    monitor_changes([X1,X2],[info(1,X1),info(2,X2)], 8,
			    [min of fd, max of fd], fd, Stream),
	    X1 #> X2, X2 #>= 5.

    Stream = [[info(1, X1{[6..9]})], [info(2, X2{[5..8]}), info(1, X1)]|More]
    X1 = X1{[6..9]}
    X2 = X2{[5..8]}