expr/preset.go

// preset.go
package expr

import "strings"

// Preset variables
const (
	preset_last_result   = "_last"
	preset_bool_shortcut = "_bool_shortcut"
	preset_import_path   = "_import_path"
)

// Initial values
const (
	init_import_path = "~/.local/lib/go-pkg/expr:/usr/local/lib/go-pkg/expr:/usr/lib/go-pkg/expr"
)

func initDefaultVars(ctx exprContext) {
	ctx.SetValue(preset_bool_shortcut, true)
	ctx.SetValue(preset_import_path, init_import_path)
}

func enable(ctx exprContext, name string) {
	if strings.HasPrefix(name, "_") {
		ctx.SetValue(name, true)
	} else {
		ctx.SetValue("_"+name, true)
	}
}

func disable(ctx exprContext, name string) {
	if strings.HasPrefix(name, "_") {
		ctx.SetValue(name, false)
	} else {
		ctx.SetValue("_"+name, false)
	}
}

func isEnabled(ctx exprContext, name string) (status bool) {
	if v, exists := ctx.GetValue(name); exists {
		if b, ok := v.(bool); ok {
			status = b
		}
	}
	return
}

func getPresetString(ctx exprContext, name string) (s string, exists bool) {
	var v any
	if v, exists = ctx.GetValue(name); exists {
		s, exists = v.(string)
	}
	return
}