Make SyntaxList implement IEnumerable<SyntaxElement>

[viclin-msft]

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.

[viclin-msft]

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());

[sloutsky]

Adding @Matt Warrenmailto:mattwar@microsoft.com

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My current workaround:

private IEnumerable 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());

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[mattwar]

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.