Foreword

This specification replaces ECMA-334:2022. Changes from the previous edition include the addition of the following:

• Binary integer literals
• Embedded digit separators in numeric literals
• Leading-digit separators in binary and hexadecimal integer literals
• out variables
• Discards
• Tuple types
• Pattern Matching
• ref locals and returns, conditional ref expressions, ref with this in extension methods, and reassignment of ref local variables
• Local Functions
• More expression-bodied members
• throw Expressions
• Generalized async return types
• async Main method
• default literal expressions
• Non-trailing named arguments
• private protected access modifier
• in parameter modifier
• readonly structs
• ref structs
• Indexing movable fixed buffer without pinning
• Initializers on stackalloc arrays
• Pattern-based fixed statements
• System.Delegate and System.Enum as class_type constraints.
• Additional generic constraints
• Allow expression variables in more locations
• Attach attributes to the backing field of auto-implemented properties
• Reduce ambiguity of overload resolution