func url(call *ast.CallExpr, args ...*ast.BasicLit) (*ast.BasicLit, error) {
val := args[0].Value
if args[0].Kind == token.QSTRING {
val = `"` + val + `"`
}
val = "url(" + val + ")"
lit := &ast.BasicLit{
Kind: token.STRING,
Value: val,
ValuePos: call.Pos(),
}
return lit, nil
}
func unit(call *ast.CallExpr, args ...*ast.BasicLit) (*ast.BasicLit, error) {
in := *args[0]
lit := &ast.BasicLit{
Kind: token.QSTRING,
ValuePos: call.Pos(),
}
switch in.Kind {
case token.UEM:
lit.Value = "em"
case token.UPX:
lit.Value = "px"
case token.UPCT:
lit.Value = "%"
case token.INT, token.FLOAT:
lit.Value = ""
case token.STRING, token.QSTRING, token.QSSTRING:
return nil, fmt.Errorf(`$number: "%s" is not a number for unit`, in.Value)
default:
return nil, errors.New("unsupported type for type-of")
}
return lit, nil
}