Files
expr/operator-context.go
T

90 lines
2.2 KiB
Go

// Copyright (c) 2024-2026 Celestino Amoroso (celestino.amoroso@gmail.com).
// All rights reserved.
// operator-context-value.go
package expr
import (
"io"
"git.portale-stac.it/go-pkg/expr/kern"
"git.portale-stac.it/go-pkg/expr/scan"
)
//-------- context term
func newContextTerm(tk *scan.Token) (inst *scan.Term) {
return &scan.Term{
Tk: *tk,
Children: make([]*scan.Term, 0, 1),
Position: scan.PosPrefix,
Priority: scan.PriIncDec,
EvalFunc: evalContextValue,
}
}
func evalContextValue(ctx kern.ExprContext, opTerm *scan.Term) (v any, err error) {
var childValue any
var sourceCtx kern.ExprContext
if len(opTerm.Children) == 0 {
sourceCtx = ctx
} else if opTerm.Children[0].Symbol() == scan.SymVariable && opTerm.Children[0].Source() == "global" {
sourceCtx = ctx.GetGlobal()
} else if childValue, err = opTerm.EvalPrefix(ctx); err == nil {
if dc, ok := childValue.(*dataCursor); ok {
sourceCtx = dc.ctx
}
} else {
return
}
if sourceCtx != nil {
if formatter, ok := sourceCtx.(kern.DictFormat); ok {
v = formatter.ToDict()
} else if formatter, ok := sourceCtx.(kern.Formatter); ok {
v = formatter.ToString(0)
} else {
// keys := sourceCtx.EnumVars(func(name string) bool { return name[0] != '_' })
keys := sourceCtx.EnumVars(nil)
d := make(map[string]any)
for _, key := range keys {
d[key], _ = sourceCtx.GetVar(key)
}
keys = sourceCtx.EnumFuncs(func(name string) bool { return true })
for _, key := range keys {
d[key], _ = sourceCtx.GetFuncInfo(key)
}
v = d
}
} else if childValue != nil {
it, ok := childValue.(kern.Iterator)
if !ok {
it, err = NewIterator(ctx, childValue, nil)
}
if err == nil {
var item any
// values := kern.NewListA()
values := kern.NewLinkedListA()
for item, err = it.Next(); err == nil; item, err = it.Next() {
// values.AppendItem(item)
values.PushBack(item)
}
if err == io.EOF {
err = nil
v = values
}
// } else {
// err = opTerm.ErrIncompatiblePrefixPostfixType(childValue)
}
} else {
err = opTerm.ErrIncompatiblePrefixPostfixType(childValue)
}
return
}
// init
func init() {
scan.RegisterTermConstructor(scan.SymDoubleDollar, newContextTerm)
}