`->i` already supports method contracts (for use wihin `object-contract`,
whose `->i` support is tested, but undocumented), which would make `->im`
possible.
Unfortunately, that support is very incomplete, missing support for using
`this` in contracts, making this `->im` (or the undocumented `->i` +
`object-contract` combo) basically useless.
Once/if that is added, then this commit would enable `->im`. Until then,
it's mostly useful for future reference (hence will be reverted).
In the meantime, it's possible to use `->i` within class/object contracts
with an explicit `this` argument, so nothing critical is lost, just a tiny
shortcut.
Port `examples`, `interactions`, etc., to use the new `examples`
form of `scribble/examples`. The main intended effect is to ensure
that errors are produced by examples only as specifically
indicated.
Adds a sealing and unsealing function to attach (or detach)
seals onto a class via impersonator properties. Since these
properties override, they do not accumulate wrappers.
Calling seal multiple times will still accumulate multiple seal
values inside the property.
A sealed class cannot be instantiated and a subclass may not
add class members that match any of the sealed names in its
sealed parent.
These functions are intended for use by TR's `sealing->/c`
contract, but are parameterized over checking functions and
could be used for other purposes.
