Eobject . identifierThe object expression must evaluate to a valid object and the identifier must refer to a valid identifier declared in the class of the object. The whole expression evaluates to the value associated with the identifier in the object.
$EanyPlacing a dollar sign before any expression in a quasi-quotation context forces evaluation.
%SpnHd?:[Vhead ! Vtail] => true if Vhead is a suspension %SpnTl?:[Vhead ! Vtail] => true if Vtail is a suspension
%iport: X => [FA ! S] FA: V => atomically appends V to the end of S %oport: [V0 V1 V2 ...] => FB FB: Y => strips and returns some elements from the input stream%iport and %oport are imperative interfaces to streams. %iport takes a reference and returns a closure and a stream. The closure FA appends its argument to Lstream whenever it is applied. If FA is ever applied to X then the stream is terminated (note: X must be the same reference).
%oport takes a list or stream and returns a closure. The closure FB strips some number of elements from the front of the stream and returns them as a list. The number returned is based on the Y argument to FB:
%iport and %oport are used by the system to merge and split streams efficiently.