Celestino Amoroso
eccb0c4dc9
Also made a litle change to scanner function moveOn(): now it moves on the last char passed and only if there are more than one chars.
78 lines
1.8 KiB
Go
78 lines
1.8 KiB
Go
// Copyright (c) 2024 Celestino Amoroso (celestino.amoroso@gmail.com).
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// All rights reserved.
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// operator-shift.go
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package expr
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//-------- bit right shift term
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func newRightShiftTerm(tk *Token) (inst *term) {
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return &term{
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tk: *tk,
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children: make([]*term, 0, 2),
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position: posInfix,
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priority: priBinShift,
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evalFunc: evalRightShift,
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}
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}
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func bitRightShift(opTerm *term, leftValue, rightValue any) (v any, err error) {
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if IsInteger(leftValue) && IsInteger(rightValue) {
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leftInt := leftValue.(int64)
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rightInt := rightValue.(int64)
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v = leftInt >> rightInt
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} else {
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err = opTerm.errIncompatibleTypes(leftValue, rightValue)
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}
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return
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}
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func evalRightShift(ctx ExprContext, opTerm *term) (v any, err error) {
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var leftValue, rightValue any
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if leftValue, rightValue, err = opTerm.evalInfix(ctx); err != nil {
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return
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}
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v, err = bitRightShift(opTerm, leftValue, rightValue)
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return
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}
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func newLeftShiftTerm(tk *Token) (inst *term) {
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return &term{
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tk: *tk,
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children: make([]*term, 0, 2),
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position: posInfix,
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priority: priBinShift,
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evalFunc: evalLeftShift,
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}
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}
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func bitLeftShift(opTerm *term, leftValue, rightValue any) (v any, err error) {
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if IsInteger(leftValue) && IsInteger(rightValue) {
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leftInt := leftValue.(int64)
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rightInt := rightValue.(int64)
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v = leftInt << rightInt
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} else {
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err = opTerm.errIncompatibleTypes(leftValue, rightValue)
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}
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return
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}
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func evalLeftShift(ctx ExprContext, opTerm *term) (v any, err error) {
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var leftValue, rightValue any
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if leftValue, rightValue, err = opTerm.evalInfix(ctx); err != nil {
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return
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}
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v, err = bitLeftShift(opTerm, leftValue, rightValue)
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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(SymDoubleGreater, newRightShiftTerm)
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registerTermConstructor(SymDoubleLess, newLeftShiftTerm)
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}
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