As it turns out, you can create a class named var and instantiate it with new var();. What influenced the C# developers to allow this to happen with var but not other keywords?
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user1306322
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var was only introduced in C# 3.0. It wasn't a keyword at all in older versions of the language. The designers presumably didn't anticipate creating a var keyword at the time they first designed the language, so code was always allowed to use it as an identifier.
That's why var is only a contextual keyword. If it were made a reserved word, existing code would break in the C# 3.0 compiler until all occurrences of var were renamed.
BoltClock
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as he said, var does not represent anything aside of implicit type – MrVoid Apr 04 '18 at 10:54
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Was there a precedent with other keywords which disallowed previously valid type names from being used? – user1306322 Apr 04 '18 at 10:54
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2@user1306322 - you can also have variables called e.g. `async`. Basically, any new keywords added after C# 1 tend to be contextual. Can't think of any that aren't. – Damien_The_Unbeliever Apr 04 '18 at 10:55
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3https://learn.microsoft.com/en-us/dotnet/csharp/language-reference/keywords/#contextual-keywords – Hans Kesting Apr 04 '18 at 10:55