func SassHandler(h SassFunc) libs.SassCallback {
return func(v interface{}, usv libs.UnionSassValue, rsv *libs.UnionSassValue) error {
if *rsv == nil {
*rsv = libs.MakeNil()
}
libCtx, ok := v.(*compctx)
if !ok {
return errors.New("libsass Context not found")
}
ctx := NewCompilerContext(libCtx.compiler)
// Cast to exported Go types
req := SassValue{value: usv}
res, err := h(ctx, req)
if err != nil {
// Returns the error to libsass Compiler
*rsv = libs.MakeError(err.Error())
// Returning an error does nothing as libsass is in charge of
// reporting error to user
return err
}
*rsv = res.Val()
return err
}
}
// Error takes a Go error and returns a libsass Error
func Error(err error) SassValue {
return SassValue{value: libs.MakeError(err.Error())}
}