Unclear TypeError thrown when field is of type Function

[jakefurler]

If I define a schema with a field of type Function, an unclear error is thrown.

/.../schemas/node_modules/typescript-json-schema/typescript-json-schema.js:421
            var indexSignatures = clazz.members.filter(function (x) { return x.kind === ts.SyntaxKind.IndexSignature; });
                                               ^

TypeError: Cannot read property 'filter' of undefined

This only occurs for recent versions of the library, introduced in #117. Without that change, I get a definition produced like this:

"Function": {
            "additionalProperties": false,
            "description": "Creates a new function.",
            "properties": {
                "__@hasInstance": {
                    "additionalProperties": false,
                    "description": "Determines whether the given value inherits from this function if this function was used\nas a constructor function.\n\nA constructor function can control which objects are recognized as its instances by\n'instanceof' by overriding this method.",
                    "type": "object"
                },
                "apply": {
                    "additionalProperties": false,
                    "description": "Calls the function, substituting the specified object for the this value of the function, and the specified array for the arguments of the function.",
                    "type": "object"
                },
                "arguments": {
                },
                "bind": {
                    "additionalProperties": false,
                    "description": "For a given function, creates a bound function that has the same body as the original function.\nThe this object of the bound function is associated with the specified object, and has the specified initial parameters.",
                    "type": "object"
                },
                "call": {
                    "additionalProperties": false,
                    "description": "Calls a method of an object, substituting another object for the current object.",
                    "type": "object"
                },
                "caller": {
                    "$ref": "#/definitions/Function"
                },
                "length": {
                    "type": "number"
                },
                "name": {
                    "description": "Returns the name of the function. Function names are read-only and can not be changed.",
                    "type": "string"
                },
                "prototype": {
                },
                "toString": {
                    "additionalProperties": false,
                    "description": "Returns a string representation of a function.",
                    "type": "object"
                }
            },
            "required": [
                "__@hasInstance",
                "apply",
                "arguments",
                "bind",
                "call",
                "caller",
                "length",
                "name",
                "prototype",
                "toString"
            ],
            "type": "object"
        },

Not sure if Functions are really supported, see #110. But the message should at least be clearer.

[domoritz]

Functions are generally not supported but Function is treated as an object. Can you try to fix the issu that you are seeing.

CC @otgerrogla

[jakefurler]

PR here: https://github.com/YousefED/typescript-json-schema/pull/137/files