Prefix keys in seqObj's seenKeys to avoid collisions

[jfirebaugh]

Otherwise, seqObj will fail for the keys in Object.getOwnPropertyNames(Object.prototype), the most likely collision being "constructor".

An alternate implementation strategy is Object.create(null), but it's not supported on IE <9, and is not possible to polyfill.

[wavebeem]

good catch, thanks. and appreciate the eye for ie compat!

[coveralls]

Coverage remained the same at 100.0% when pulling 45acb6a on mapbox:seqObj-special-keys into 65022cb on jneen:master.

[coveralls]

Coverage remained the same at 100.0% when pulling 45acb6a on mapbox:seqObj-special-keys into 65022cb on jneen:master.

[coveralls]

Coverage remained the same at 100.0% when pulling 45acb6a on mapbox:seqObj-special-keys into 65022cb on jneen:master.

[coveralls]

Coverage remained the same at 100.0% when pulling 45acb6a on mapbox:seqObj-special-keys into 65022cb on jneen:master.

[coveralls]

Coverage remained the same at 100.0% when pulling c506e0d on mapbox:seqObj-special-keys into 65022cb on jneen:master.

[wavebeem]

wow idk what's going on with coveralls there lol.

i'll merge this and release when i get some free time.

[wavebeem]

This solution should be good for 99% of cases but I think it would be more correct to use hasOwnProperty for this check since technically someone could add $constructor or similar to Object.prototype.

hasOwnProperty goes back to ES3 so it should work in all environments Parsimmon supports.

Also, would you mind fixing this in bitSeqObj too?

[wavebeem]

Thanks for the bugfixes!