Evaluation Automaton — for ... to ... do

Documentation status: reference — see Maturity and evidence.

The bounded form is present in the current FPL grammar:

for variable := lower to upper do expression

Protocol

evaluate lower
  -> evaluate upper
  -> initialize loop binding
  -> test bound
  -> evaluate body
  -> advance binding
  -> resume at test
  -> complete

The bounds are expressions themselves and are evaluated before iteration.

Context

The loop variable belongs to the protocol's evaluation environment. The body can therefore use the same resolution mechanisms, value stacks, and calls as other FPLN expressions.

Documentation scope

This page describes the language semantics, not the identity of the private class that executes the construct.