44 lines
976 B
Go
44 lines
976 B
Go
// Copyright (c) 2024-2026 Celestino Amoroso (celestino.amoroso@gmail.com).
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// All rights reserved.
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// operator-iter-value.go
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package expr
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import (
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"git.portale-stac.it/go-pkg/expr/kern"
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"git.portale-stac.it/go-pkg/expr/scan"
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)
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//-------- iter value term
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func newIterValueTerm(tk *scan.Token) (inst *scan.Term) {
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return &scan.Term{
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Tk: *tk,
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Children: make([]*scan.Term, 0, 1),
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Position: scan.PosPrefix,
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Priority: scan.PriDereference,
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EvalFunc: evalIterValue,
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}
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}
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func evalIterValue(ctx kern.ExprContext, opTerm *scan.Term) (v any, err error) {
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var childValue any
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if childValue, err = opTerm.EvalPrefix(ctx); err != nil {
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return
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}
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if it, ok := childValue.(kern.Iterator); ok {
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v, err = it.Current()
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} else {
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err = opTerm.ErrIncompatiblePrefixPostfixType(childValue)
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}
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return
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}
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// init
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func init() {
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// registerTermConstructor(SymOpenClosedRound, newIterValueTerm)
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scan.RegisterTermConstructor(scan.SymDereference, newIterValueTerm)
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}
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