Re: [swift-evolution] Optional dictionary subscripts
> I think this would be the standard syntax:
>
> if let value = key.map({ dict[$0] }) {
>
> }
In this case, I think you actually want a flatMap, to merge the two `nil` cases
instead of nesting them.
if let value = key.flatMap({ dict[$0] }) {
}
I wish that could be this, though:
if let value = key.flatMap(dict.subscript) {
}
In any case, I think two different approaches to do this (chained `if let` and
`flatMap`) are probably enough; we don't need a third.
--
Brent Royal-Gordon
Architechies
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Re: [swift-evolution] Optional dictionary subscripts
if let value = map(key) { dict($0) }
Félix
> Le 22 déc. 2015 à 13:00:45, Erica Sadun via swift-evolution
> a écrit :
>
> if let key = key, value = dict[key] {
>...whatever...
> }
>
> seems to work fine without introducing a new construct
>
> -- E, waving hi to John
>
>
>> On Dec 22, 2015, at 4:37 AM, John Holdsworth via swift-evolution
>> wrote:
>>
>> This isn’t the most compelling of ideas but a couple of times I’ve found
>> myself writing:
>>
>> if let value = key != nil ? dict[key] : nil {…
>>
>> and was wondering if the syntax could be:
>>
>> if let value = dict[key?] {…
>>
>> The key for dictionaries could be made optional in stdlib but this is
>> probably best implemented in the compiler for safety.
>>
>> Cheers
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>
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Re: [swift-evolution] Optional dictionary subscripts
I think this would be the standard syntax:
if let value = key.map({ dict[$0] }) {
}
> On Dec 22, 2015, at 10:33 AM, Félix Cloutier via swift-evolution
> wrote:
>
> if let value = map(key) { dict($0) }
>
> Félix
>
>> Le 22 déc. 2015 à 13:00:45, Erica Sadun via swift-evolution
>> a écrit :
>>
>> if let key = key, value = dict[key] {
>> ...whatever...
>> }
>>
>> seems to work fine without introducing a new construct
>>
>> -- E, waving hi to John
>>
>>
>>> On Dec 22, 2015, at 4:37 AM, John Holdsworth via swift-evolution
>>> wrote:
>>>
>>> This isn’t the most compelling of ideas but a couple of times I’ve found
>>> myself writing:
>>>
>>> if let value = key != nil ? dict[key] : nil {…
>>>
>>> and was wondering if the syntax could be:
>>>
>>> if let value = dict[key?] {…
>>>
>>> The key for dictionaries could be made optional in stdlib but this is
>>> probably best implemented in the compiler for safety.
>>>
>>> Cheers
>>> ___
>>> swift-evolution mailing list
>>> swift-evolution@swift.org
>>> https://lists.swift.org/mailman/listinfo/swift-evolution
>>
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-Dave
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Re: [swift-evolution] Optional dictionary subscripts
if let key = key, value = dict[key] {
...whatever...
}
seems to work fine without introducing a new construct
-- E, waving hi to John
> On Dec 22, 2015, at 4:37 AM, John Holdsworth via swift-evolution
> wrote:
>
> This isn’t the most compelling of ideas but a couple of times I’ve found
> myself writing:
>
> if let value = key != nil ? dict[key] : nil {…
>
> and was wondering if the syntax could be:
>
> if let value = dict[key?] {…
>
> The key for dictionaries could be made optional in stdlib but this is
> probably best implemented in the compiler for safety.
>
> Cheers
> ___
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> swift-evolution@swift.org
> https://lists.swift.org/mailman/listinfo/swift-evolution
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[swift-evolution] Optional dictionary subscripts
This isn’t the most compelling of ideas but a couple of times I’ve found myself
writing:
if let value = key != nil ? dict[key] : nil {…
and was wondering if the syntax could be:
if let value = dict[key?] {…
The key for dictionaries could be made optional in stdlib but this is probably
best implemented in the compiler for safety.
Cheers
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