diff options
Diffstat (limited to 'resolve/resolve.go')
| -rw-r--r-- | resolve/resolve.go | 40 |
1 files changed, 30 insertions, 10 deletions
diff --git a/resolve/resolve.go b/resolve/resolve.go index 0bc9ac0..51325bd 100644 --- a/resolve/resolve.go +++ b/resolve/resolve.go @@ -765,7 +765,9 @@ func (r *resolver) function(pos syntax.Position, name string, function *syntax.F r.push(b) var seenOptional bool - var star, starStar *syntax.Ident // *args, **kwargs + var star *syntax.UnaryExpr // * or *args param + var starStar *syntax.Ident // **kwargs ident + var numKwonlyParams int for _, param := range function.Params { switch param := param.(type) { case *syntax.Ident: @@ -786,7 +788,7 @@ func (r *resolver) function(pos syntax.Position, name string, function *syntax.F if starStar != nil { r.errorf(param.OpPos, "optional parameter may not follow **%s", starStar.Name) } else if star != nil { - r.errorf(param.OpPos, "optional parameter may not follow *%s", star.Name) + numKwonlyParams++ } if id := param.X.(*syntax.Ident); r.bind(id) { r.errorf(param.OpPos, "duplicate parameter: %s", id.Name) @@ -794,30 +796,48 @@ func (r *resolver) function(pos syntax.Position, name string, function *syntax.F seenOptional = true case *syntax.UnaryExpr: - // *args or **kwargs - id := param.X.(*syntax.Ident) + // * or *args or **kwargs if param.Op == syntax.STAR { if starStar != nil { - r.errorf(param.OpPos, "*%s parameter may not follow **%s", id.Name, starStar.Name) + r.errorf(param.OpPos, "* parameter may not follow **%s", starStar.Name) } else if star != nil { r.errorf(param.OpPos, "multiple * parameters not allowed") } else { - star = id + star = param } } else { if starStar != nil { r.errorf(param.OpPos, "multiple ** parameters not allowed") - } else { - starStar = id } + starStar = param.X.(*syntax.Ident) } + } + } + + // Bind the *args and **kwargs parameters at the end, + // so that regular parameters a/b/c are contiguous and + // there is no hole for the "*": + // def f(a, b, *args, c=0, **kwargs) + // def f(a, b, *, c=0, **kwargs) + if star != nil { + if id, _ := star.X.(*syntax.Ident); id != nil { + // *args if r.bind(id) { r.errorf(id.NamePos, "duplicate parameter: %s", id.Name) } + function.HasVarargs = true + } else if numKwonlyParams == 0 { + r.errorf(star.OpPos, "bare * must be followed by optional parameters") } } - function.HasVarargs = star != nil - function.HasKwargs = starStar != nil + if starStar != nil { + if r.bind(starStar) { + r.errorf(starStar.NamePos, "duplicate parameter: %s", starStar.Name) + } + function.HasKwargs = true + } + + function.NumKwonlyParams = numKwonlyParams r.stmts(function.Body) // Resolve all uses of this function's local vars, |