Levels of knowing a programming language

1) You can read and understand what the code does

2) You modify existing code to do something different

3) You can write code from scratch that does what you want

4) You can fully utilize the language syntax and its libraries

5) You write programs with the language for things people don’t even imagine and use it in ways people barely believe

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What is => ? What is it called and what does it do? C#.

The ‘lambda operator’. It’s read as ‘goes to’. As in, x => 2 * x is read as “x goes to 2 times x .”

A lambda expression is an anonymous function that you can use to create delegates or expression tree types. By using lambda expressions, you can write local functions that can be passed as arguments or returned as the value of function calls. Lambda expressions are particularly helpful for writing LINQ query expressions.

To create a lambda expression, you specify input parameters (if any) on the left side of the lambda operator =>, and you put the expression or statement block on the other side. For example, the lambda expression x => x * x specifies a parameter that’s named x and returns the value of x squared.

via ms docs