Inline property initialisation and trailing comma

by

I find the above typo in my code quite a lot. I’m always suprised that the compiler doesn’t seem to care about this. Why is the above not a syntax errror?

Because the people designing the C# syntax grammar were smart enough to learn the lessons from other programming languages which didn’t allow the dangling comma, to the constant irritation of programmers in those languages.

For example, ECMAScript (JavaScript) was silent on the issue initially, and so naturally some implementations (SpiderMonkey in Firefox, Opera’s JavaScript, etc.) allowed them while others (Microsoft’s JScript) didn’t. And so this led to a spate of “why doesn’t this work in IE” questions here and elsewhere. (Fortunately, ECMAScript 5 explicitly allows them, and IE8 finally supports them in object initializers — IE8 still treats array initializers in a non-standard way, though to be fair the dangling comma for those was only clarified in ECMAScript 5, too.)

You find this in lots of other places in the C# grammar too, like enums and array initializers.

More Related Contents:

  1. C# Expressional if statements, possible expansion? [closed]
  2. All possible array initialization syntaxes
  3. C# – Keyword usage virtual+override vs. new
  4. What is special about numbers starting with zero?
  5. What does the tilde before a function name mean in C#?
  6. implicit operator using interfaces
  7. Difference between wiring events with and without “new”
  8. Delegate caching behavior changes in Roslyn
  9. In c# what does ‘where T : class’ mean?
  10. How does creating a instance of class inside of the class itself works?
  11. What does the tilde mean in an expression? [duplicate]
  12. Why is Main method private?
  13. What’s the false operator in C# good for?
  14. C# compiler bug? Why doesn’t this implicit user-defined conversion compile?
  15. Could not load file or assembly … The parameter is incorrect
  16. C# binary literals
  17. Compiler Value Type Resolution and Hardcoded “0” Integer Values
  18. TargetedPatchingOptOut: “Performance critical to inline across NGen image boundaries”?
  19. What does the @ prefix do on string literals in C#
  20. C# using numbers in an enum
  21. Why can’t I use the array initializer with an implicitly typed variable?
  22. Is this pattern matching expression equivalent to not null
  23. Mono Compiler as a Service (MCS)
  24. The name ‘str’ does not exist in the current context
  25. Why does this (null || !TryParse) conditional result in “use of unassigned local variable”?
  26. What’s the difference between ‘int?’ and ‘int’ in C#?
  27. How do generics get compiled by the JIT compiler?
  28. Why can’t we define a variable inside a while loop?
  29. C# Compiler should give warning but doesn’t?
  30. Why and how does C# allow accessing private variables outside the class itself when it’s within the same containing class?

Leave a Comment