Problem with source-map-loader when using webpack: "The keyword 'interface' is reserved"

[sledorze]

(Issue using io-ts 0.5.0, 0.5.1 and 0.6.0)
The problem is that Webpack transform userland code of io-ts like this:

import { _A, array, boolean, failure, interface, intersection, number, partial, recursion, string, success } from 'io-ts/index';

importing directly 'interface' even if the original code was using it like so:

import * as t from 'io-ts';

const myType = t.interface({
...
})

Resulting in an error when source-map-loader kicks in:

The keyword 'interface' is reserved (1:38) You may need an appropriate loader to handle this file type.

Also this generates a visual error in visual code studio.

A solution would be to provide an alternative keyword.

[sledorze]

Actually using
t._interface
is ALREADY available, so that's all I needed.

[sledorze]

I am reopening this issue because, the same problem happens with
t.null

[sledorze]

@gcanti the problem is pretty general in this setting.
Maybe we can double all the exported definitions whose names match reserved keywords?

[gcanti]

@sledorze Could you please put up a repo reproducing the error?

Based on your description though, it doesn't seem an issue with io-ts, it rather seems a bug in the transformer

[gcanti]

@sledorze anyway I'm ok with exporting some alias, I propose

• type as an alias of interface
• nullType as an alias of null

does undefined raise an error too? (EDIT it shouldn't)

[sledorze]

@gcanti undefined is 'correctly webpacked' to something like: undefined as undefined$1
I think it could help a lot of people.
nullType is ok
type may also be a reserved keyword, the existing _interface is fine to me but if we aim at homogeneity, why not interfaceType ?

[gcanti]

type is not a reserved keyword. Also seems appropriate

type Person = {
  name: string
}

const Person = t.type({
  name: t.string
})

[sledorze]

It is a typescript keyword, not a js one, you're right
Hoping it will not pose an issue with tooling then :)