Make SyntaxList implement IEnumerable<SyntaxElement>

[Victor Lin]

Currently, SyntaxList does not support LINQ queries, e.g.

SyntaxList elements = ...
elements.Select(x => x.ToString());

This can be supported by having the class implement IEnumerable<SyntaxElement>.

It is comparable to Microsoft.CodeAnalysis.SyntaxList.

[Victor Lin]

My current workaround:

private IEnumerable<SyntaxElement> GetEnumerableElements(SyntaxList list)
{
    foreach (var element in list)
    {
        yield return element.GetChild(0);  // element is SeparatedElement; the first child is the actual item in list
    }
}

SyntaxList elements = ...
GetEnumerableElements(elements).Select(x => x.ToString());

[Alexander Sloutsky]

Adding @matt Warren<mailto:[e-mail]> // Sent from phone

…

________________________________ From: Victor Lin <[e-mail]> Sent: Wednesday, December 30, 2020 10:22:05 PM To: microsoft/Kusto-Query-Language <[e-mail]> Cc: Subscribed <[e-mail]> Subject: Re: [microsoft/Kusto-Query-Language] Make SyntaxList implement IEnumerable<SyntaxElement> (#41) My current workaround: private IEnumerable<SyntaxElement> GetEnumerableElements(SyntaxList list) { foreach (var element in list) { yield return element.GetChild(0); // element is SeparatedElement; the first child is the actual item in list } } SyntaxList elements = ... GetEnumerableElements(elements).Select(x => x.ToString()); — You are receiving this because you are subscribed to this thread. Reply to this email directly, view it on GitHub<https://nam06.safelinks.protection.outlook.com/?url=https%3A%2F%2Fgithub.com%2Fmicrosoft%2FKusto-Query-Language%2Fissues%2F41%23issuecomment-752746543&data=04%7C01%7CAlexander.Sloutsky%40microsoft.com%7C4689bd1900aa403cdabf08d8ad00931f%7C72f988bf86f141af91ab2d7cd011db47%7C1%7C0%7C637449565279496978%7CUnknown%7CTWFpbGZsb3d8eyJWIjoiMC4wLjAwMDAiLCJQIjoiV2luMzIiLCJBTiI6Ik1haWwiLCJXVCI6Mn0%3D%7C1000&sdata=X66v1ol9aW8mdza9TSDtPU%2FUtj7pQJNAD5obib4hyBE%3D&reserved=0>, or unsubscribe<https://nam06.safelinks.protection.outlook.com/?url=https%3A%2F%2Fgithub.com%2Fnotifications%2Funsubscribe-auth%2FAEH2NB2AND6CTKURYDXIJ6DSXODW3ANCNFSM4VOVUMQQ&data=04%7C01%7CAlexander.Sloutsky%40microsoft.com%7C4689bd1900aa403cdabf08d8ad00931f%7C72f988bf86f141af91ab2d7cd011db47%7C1%7C0%7C637449565279496978%7CUnknown%7CTWFpbGZsb3d8eyJWIjoiMC4wLjAwMDAiLCJQIjoiV2luMzIiLCJBTiI6Ik1haWwiLCJXVCI6Mn0%3D%7C1000&sdata=5VtL1s7qWEYYMoPYyrF9cukxFGaAiQZXuIyx4ykPpyQ%3D&reserved=0>.

[Matt Warren]

The type SyntaxList is an abstract base for SyntaxList<T>. SyntaxList<T> already does implement IEnumerable<T> via IReadOnlyList<T>. However, if both the base type and subtype implement different IEnumerable<T> it confuses LINQ and blocks uses of extension methods on any SyntaxList<T> subtype.

SyntaxList does implement the enumerable pattern, though. That lets you use foreach, but not other LINQ methods.