Files
expr/operand-literal.go
T
camoroso 8e596d5979 several changes:
1. moved scan/symbol.go to new package sym and adapted all files that reference Symbol type and its values.
2. new type interval defined by begin, end and step values.
3. replaced operator-range.go with operator-interval.go.
4. replaced range operator begin:end with begin..end..step.
5. new implementation of sub-collection extraction based on new interval literal.
2026-07-27 16:01:52 +02:00

51 lines
1.2 KiB
Go

// Copyright (c) 2024-2026 Celestino Amoroso (celestino.amoroso@gmail.com).
// All rights reserved.
// operand-literal.go
package expr
import (
"git.portale-stac.it/go-pkg/expr/kern"
"git.portale-stac.it/go-pkg/expr/scan"
"git.portale-stac.it/go-pkg/expr/sym"
"git.portale-stac.it/go-pkg/expr/types/fract"
)
// -------- literal term
func newLiteralTerm(tk *scan.Token) *scan.Term {
if tk.Sym == sym.SymFraction {
if v, isString := tk.Value.(string); isString {
var err error
if tk.Value, err = fract.MakeGeneratingFraction(v); err != nil {
return nil
}
}
}
return &scan.Term{
Tk: *tk,
Parent: nil,
Children: nil,
Position: scan.PosLeaf,
Priority: scan.PriValue,
EvalFunc: evalLiteral,
}
}
// -------- eval func
func evalLiteral(ctx kern.ExprContext, opTerm *scan.Term) (v any, err error) {
v = opTerm.Tk.Value
return
}
// init
func init() {
scan.RegisterTermConstructor(sym.SymString, newLiteralTerm)
scan.RegisterTermConstructor(sym.SymInteger, newLiteralTerm)
scan.RegisterTermConstructor(sym.SymFloat, newLiteralTerm)
scan.RegisterTermConstructor(sym.SymFraction, newLiteralTerm)
scan.RegisterTermConstructor(sym.SymBool, newLiteralTerm)
scan.RegisterTermConstructor(sym.SymKwNil, newLiteralTerm)
}