Known as Short Canonical Active
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List [A|B] .(A,B) always
Curly brackets {A} {}(A) always
Subscripted variable X[...] subscript(X, [...]) default
Subscripted struct S[...] subscript(S, [...]) default
Declared structure f{...} with(f, [...]) default
Attributed variable X{...} 'with attributes'(X, [...]) default
Variable functor X(...) apply(X, [...]) optional

Here A,B stands for arbitrary terms, X for a variable, S for a compound term
in canoncial syntax, f for an arbitrary functor, and the ellipsis for
a comma-separated sequence of arbitrary terms.