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I have a question concerning get0/read and call (I am using Quintus Prolog):

(1) A predicate f is defined with
	:- op(700,fx,f).
(2) A prompt requests input from the terminal:
	a) when I use read/1 to get input, eg. f tata, and call/1 on the
	   input, the call takes place, ie., execution of predicate f occurs
	   with input tata;
	b) when I decided to use the prompt library which uses a loop of get0/1
	   to build up a list of input, and used atom_chars to convert list
	   into atom, the call/1 on this term `f tata' resulted in prediciate
	   'f data' undefined.

	Can someone explain to me what the difference between these two cases ?
	It seemed the blank made a difference in the two cases ?

	cheers
	duc@COS.COM