Not sure I like this without tail recursion
Posted by jpluimers on 2024/05/07
A while ago Andy Gocke posted this bit of C# 11 code:
[Wayback/Archive] Andy Gocke on Twitter: “Can’t believe none of that “C# is turning into F#” people have noted that this is legal code in C# 11″
with code referenced from [Wayback/Archive] Andy Gocke on Twitter: “@evntdrvn Oops, here you go”.
A day later he posted this important addition:
[Wayback/Archive] Andy Gocke on Twitter: “PSA: please don’t actually use recursion to sum an array, use a loop or LINQ. Recursion is best for recursive data structures (like trees)“
In [Wayback/Archive] SharpLab you can see the syntactic C# sugar
int Sum(Span s) => s switch { [] => 0, [var x, .. var xs] => x + Sum(xs) };
is converted into this C# code:
private int Sum(Span s) { int length = s.Length; if (length != 0) { int num = s[0]; Span s2 = s.Slice(1, length - 1); return num + Sum(s2); } return 0; }
The compiler could convert this tail recursion into an iteration. Hopefully one day it does.
–jeroen
The Wiert Corner - irregular stream of stuff 
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