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perform:withArguments: and collection

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Peter Uhnak

perform:withArguments: and collection

Hi,

Apparently sending #perform:withArguments: and using OrderedCollection leads to PrimitiveFailed.

I can recast it, but maybe we can just add

(argArray isArray)
ifFalse: [ ^ self error: 'Arguments must be instance of Array' ]

to make the error less cryptic.

(or allow OrderedCollection, but since the operation is done in VM it might be needlessly more work.)

Peter

Eliot Miranda-2

Re: perform:withArguments: and collection

On Sun, Mar 12, 2017 at 3:16 PM, Peter Uhnak <[hidden email]> wrote:

Hi,

Apparently sending #perform:withArguments: and using OrderedCollection leads to PrimitiveFailed.

I can recast it, but maybe we can just add

(argArray isArray)
ifFalse: [ ^ self error: 'Arguments must be instance of Array' ]

+1. The alternative is having the primitive failure code test for the argument being sequence able and doing it for you:

perform: selector withArguments: argArray inSuperclass: lookupClass

"NOTE: This is just like perform:withArguments:, except that

the message lookup process begins, not with the receivers's class,

but with the supplied superclass instead. It will fail if lookupClass

cannot be found among the receiver's superclasses.

Primitive. Essential. See Object documentation whatIsAPrimitive."

<primitive: 100>

argArray isArray ifFalse:

[(argArray isCollection and: [argArray isSequenceable]) ifTrue:

[^self perform: selector withArguments: argArray asArray inSuperclass: lookupClass].

^self error: 'argArray argument must be an Array'].

selector isSymbol ifFalse:

[^self error: 'selector argument must be a Symbol'].

selector numArgs = argArray size ifFalse:

[^self error: 'incorrect number of arguments'].

(self class == lookupClass or: [self class inheritsFrom: lookupClass]) ifFalse:

[^self error: 'lookupClass is not in my inheritance chain'].

(self class lookupMethodFor: selector ifAbsent: nil) ifNotNil:

[:method| | overflowArgs |

(method numArgs = argArray size

and: [argArray size >= 15]) ifTrue:

[overflowArgs := argArray copyFrom: 1 to: 15.

overflowArgs at: 15 put: (argArray copyFrom: 15 to: overflowArgs size).

^self

perform: selector

withArguments: overflowArgs

inSuperclass: lookupClass]].

self primitiveFailed

to make the error less cryptic.

(or allow OrderedCollection, but since the operation is done in VM it might be needlessly more work.)

Right. IMO, it's a bad idea putting knowledge of OrderedCollection's representation in the VM.

Peter

_,,,^..^,,,_

best, Eliot