[Go] Type signature error

[jonlundy]

Hi, the commit here: https://github.com/antlr/antlr4/commit/c96c9ccea0be86f5dbc473052893674759dcc881

the CharStream signature for GetTextFromInterval(Interval) string https://github.com/antlr/antlr4/blob/dev/runtime/Go/antlr/v4/char_stream.go#L11

seems to have missed changing the pointer for NewInputStream(data string) *InputStream https://github.com/antlr/antlr4/blob/dev/runtime/Go/antlr/v4/input_stream.go#L48

[jimidle]

func (is *InputStream) GetTextFromInterval(i Interval) string {
    return is.GetText(i.Start, i.Stop)
}
...

func (c *CommonTokenStream) GetTextFromInterval(interval Interval) string {

CharStream is an interface. Can you elaborate on what you mean?

[bcparkison]

I might be hitting this. I'm following this example: https://blog.gopheracademy.com/advent-2017/parsing-with-antlr4-and-go/

And, I'm hitting this error:

cannot use is (variable of type *"github.com/antlr4-go/antlr".InputStream) as "github.com/antlr4-go/antlr/v4".CharStream value in argument to parser.NewCalcLexer: *"github.com/antlr4-go/antlr".InputStream does not implement "github.com/antlr4-go/antlr/v4".CharStream (wrong type for method GetTextFromInterval)
        have GetTextFromInterval(*"github.com/antlr4-go/antlr".Interval) string
        want GetTextFromInterval("github.com/antlr4-go/antlr/v4".Interval) string compiler[InvalidIfaceAssign](https://pkg.go.dev/golang.org/x/tools/internal/typesinternal#InvalidIfaceAssign)

AFAICT, the only difference between what it has and what it wants is the "v4" at the end.

[jimidle]

The article is out of date. please read the go README and switch to the new repo for importing the go runtime module. You also need antlr 4.13.1

[bcparkison]

Sorry for the false alarm! I'm learning Go and Antlr at the same time, and made a silly mistake. Thanks for pointing me in the right direction!