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Remove some details that aren't essential to know at this point

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Carol (Nichols || Goulding) 2016-07-18 20:46:01 -04:00
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src/ch04-01-anatomy-of-a-rust-program.md
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@ -107,19 +107,6 @@ let x = 2 + 3;
The expression `2 + 3` would evaluate to `5`, which would in turn be stored in The expression `2 + 3` would evaluate to `5`, which would in turn be stored in
the `x` variable binding. the `x` variable binding.
More generally, `let` statements take the form:
```text
let PATTERN = EXPRESSION;
```
*Patterns* are part of the ‘pattern matching’ feature of Rust. If you have
worked with regular expressions, you can think of patterns like a regular
expression that works on values in your program instead of characters in text.
A name like `x` is a particularly humble form of pattern; it will always match
and gets all the parts of the expression as its value. Patterns are a big part
of Rust, and we’ll see more complex and powerful patterns as we go along.
#### Printing to the Screen with a Macro #### Printing to the Screen with a Macro
The next line of our program is: The next line of our program is:
@ -164,8 +151,7 @@ The value of x is 5, and the value of y is 10
Think of `{}` as little crab pincers, holding a value in place. The first `{}` Think of `{}` as little crab pincers, holding a value in place. The first `{}`
holds the first value after the format string, the second set holds the second holds the first value after the format string, the second set holds the second
value, and so on. The `{}` placeholder has a number of more advanced formatting value, and so on.
options that we’ll discuss later.
After the `println!` macro, we match the opening curly brace that declared the After the `println!` macro, we match the opening curly brace that declared the
`main()` function with a closing curly brace to declare the end of the function: `main()` function with a closing curly brace to declare the end of the function: