stv.SetAssignable()
		}
		if tv.HasOk() {
			stv.SetHasOk()
		}
		x.SetTypeInfo(stv)
	}
}

func (check *Checker) recordBuiltinType(f syntax.Expr, sig *Signature) {
	// f must be a (possibly parenthesized, possibly qualified)
	// identifier denoting a built-in (including unsafe's non-constant
	// functions Add and Slice): record the signature for f and possible
	// children.
	for {

}

// An LParen represents the beginning of a parenthesized line block.
// It is a place to store suffix comments.
type LParen struct {
	Comments
	Pos Position
}

func (x *LParen) Span() (start, end Position) {
	return x.Pos, x.Pos.add(")")
}

// An RParen represents the end of a parenthesized line block.
// It is a place to store whole-line (before) comments.

}

// LiteralList is a type for parsed SQL lists literals
type LiteralList []string

// Capture interface used by participle
func (ls *LiteralList) Capture(values []string) error {
	// Remove enclosing parenthesis.
	n := len(values[0])
	r := values[0][1 : n-1]
	// Translate doubled quotes
	*ls = LiteralList(strings.Split(r, ","))
	return nil
}

// ObjectKey is a type for parsed strings occurring in key paths

		Code:           "ParseExpectedLeftParenAfterCast",
		Description:    "Did not find expected the left parenthesis in the SQL expression.",
		HTTPStatusCode: http.StatusBadRequest,
	},
	ErrParseExpectedLeftParenValueConstructor: {
		Code:           "ParseExpectedLeftParenValueConstructor",
		Description:    "Did not find expected the left parenthesis in the SQL expression.",
		HTTPStatusCode: http.StatusBadRequest,
	},

You only give `Depends` a single parameter.

This parameter must be something like a function.

You **don't call it** directly (don't add the parenthesis at the end), you just pass it as a parameter to `Depends()`.

And that function takes parameters in the same way that *path operation functions* do.

!!! tip

		return "key/value association"
	case *ast.LabeledStmt:
		return "statement label"
	case *ast.MapType:
		return "map type"
	case *ast.Package:
		return "package"
	case *ast.ParenExpr:
		return "parenthesized " + NodeDescription(n.X)
	case *ast.RangeStmt:
		return "range loop"
	case *ast.ReturnStmt:
		return "return statement"
	case *ast.SelectStmt:
		return "select statement"
	case *ast.SelectorExpr:

		p.lex()
		if p.tok == "!" {
			panic(&SyntaxError{Offset: p.pos, Err: "double negation not allowed"})
		}
		return not(p.atom())
	}
	return p.atom()
}

// atom parses a tag or a parenthesized expression.
// On entry, the next input token HAS been lexed.
// On exit, the next input token has been lexed and is in p.tok.
func (p *exprParser) atom() Expr {
	// first token already in p.tok
	if p.tok == "(" {

		tokens = append(tokens, substitution...)
	}
	in.Push(NewSlice(in.Base(), in.Line(), tokens))
}

// argsFor returns a map from formal name to actual value for this argumented macro invocation.
// The opening parenthesis has been absorbed.
func (in *Input) argsFor(macro *Macro) map[string][]Token {
	var args [][]Token
	// One macro argument per iteration. Collect them all and check counts afterwards.
	for argNum := 0; ; argNum++ {

		return check.instantiatedType(e.X, syntax.UnpackListExpr(e.Index), def)

	case *syntax.ParenExpr:
		// Generic types must be instantiated before they can be used in any form.
		// Consequently, generic types cannot be parenthesized.
		return check.definedType(e.X, def)

	case *syntax.ArrayType:
		typ := new(Array)
		setDefType(def, typ)
		if e.Len != nil {
			typ.len = check.arrayLength(e.Len)
		} else {
			// [...]array

		return check.instantiatedType(ix, def)

	case *ast.ParenExpr:
		// Generic types must be instantiated before they can be used in any form.
		// Consequently, generic types cannot be parenthesized.
		return check.definedType(e.X, def)

	case *ast.ArrayType:
		if e.Len == nil {
			typ := new(Slice)
			setDefType(def, typ)
			typ.elem = check.varType(e.Elt)
			return typ
		}