IMPORT /check should use script checksum

[Siskin-Bot]

Submitted by: BrianH

The script checksums in #1685 are much faster and more convenient than the method that the IMPORT /check option uses now. If we have IMPORT/check verify the checksum it will add a valuable feature: Not only is the module script verified to not be accidentally corrupted (#1685), but we can verify that it is the same module script we are expecting to use here. All you need to do is copy the checksum from the generated source to your Needs header, after the module reference. The system will do the rest.

It is probably a good idea to have a failed /check generate the same error it does now ('access 'invalid-check) so we can distinguish it from the simple corruption errors of #1685 ('syntax 'bad-checksum).

; Desired behavior

>> a: save/header none [print "Hello REBOL!"] [type: module checksum: true]
== #{
5245424F4C205B0A20202020747970653A206D6F64756C650A20202020636865
636B73756D3A20237B3444433843394545303431343034373038324646363045
36413236413930384443373837334643447D0A5D0A7072696E74202248656C6C
6F205245424F4C21220A
}

>> to-string a
== {REBOL [
    type: module
    checksum: #{4DC8C9EE0414047082FF60E6A26A908DC7873FCD}
]
print "Hello REBOL!"
}

>> c: select first load/header a 'checksum
== #{4DC8C9EE0414047082FF60E6A26A908DC7873FCD}

>> sys/load-module/check a c
Hello REBOL!
== [none make module! [
    ]]

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^{Imported from: CureCode [ Version: alpha 107 Type: Wish Platform: All Category: Mezzanine Reproduce: Always Fixed-in:alpha 108 ]
Imported from: metaeducation#1686}

Comments:

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Rebolbot added the Type.wish on Jan 12, 2016

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