expr/kern/control.go

64 lines
1.3 KiB
Go

// Copyright (c) 2024 Celestino Amoroso (celestino.amoroso@gmail.com).
// All rights reserved.
// control.go
package kern
import "strings"
// Preset control variables
const (
ControlPreset = "_preset"
ControlLastResult = "last"
ControlBoolShortcut = "_bool_shortcut"
ControlSearchPath = "_search_path"
ControlParentContext = "_parent_context"
ControlStdout = "_stdout"
)
// Other control variables
const (
ControlExportAll = "_export_all"
)
// Initial values
const (
init_search_path = "~/.local/lib/go-pkg/expr:/usr/local/lib/go-pkg/expr:/usr/lib/go-pkg/expr"
)
func CtrlIsEnabled(ctx ExprContext, name string) (status bool) {
var v any
var exists bool
if !strings.HasPrefix(name, "_") {
name = "_" + name
}
if v, exists = ctx.GetVar(name); !exists {
if globalCtx := ctx.GetGlobal(); globalCtx != nil {
v, exists = globalCtx.GetVar(name)
}
}
if exists {
if b, ok := v.(bool); ok {
status = b
}
}
return
}
func SetCtrl(ctx ExprContext, name string, value any) (current any) {
current, _ = ctx.GetVar(name)
ctx.UnsafeSetVar(name, value)
return
}
func InitDefaultVars(ctx ExprContext) {
if _, exists := ctx.GetVar(ControlPreset); exists {
return
}
ctx.UnsafeSetVar(ControlPreset, true)
ctx.UnsafeSetVar(ControlBoolShortcut, true)
ctx.UnsafeSetVar(ControlSearchPath, init_search_path)
}