A.13 library(dcg/high_order): High order grammar operations
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      • The SWI-Prolog library
        • library(dcg/high_order): High order grammar operations
          • sequence//2
          • sequence//3
          • sequence//5
          • optional//2
          • foreach//2
          • foreach//3
    • Packages
Availability::- use_module(library(dcg/high_order)).
Source[semidet]sequence(:Start, :Element, :Sep, :End, ?List)//
Match or generate a sequence of Element enclosed by Start end End, where each pair of elements is separated by Sep. More formally, it matches the following sequence:
Start, Element?, (Sep,Element)*, End

The example below matches a Prolog list of integers:

?- phrase(sequence(("[",blanks),
                   number, (",",blanks),
                   (blanks,"]"), L),
                   `[1, 2, 3 ] a`, Tail).
L = [1, 2, 3],
Tail = [32, 97].