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Formatter (#51)

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Enforce consistent formatting use `dprint`
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Luca Palmieri
2024-05-24 17:00:03 +02:00
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commit 99591a715e
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book/src/02_basic_calculator/03_if_else.md
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@@ -1,6 +1,6 @@
# Control flow, part 1
All our programs so far have been pretty straightforward.
All our programs so far have been pretty straightforward.\
A sequence of instructions is executed from top to bottom, and that's it.
It's time to introduce some **branching**.
@@ -23,7 +23,7 @@ This program will print `number is smaller than 5` because the condition `number
### `else` clauses
Like most programming languages, Rust supports an optional `else` branch to execute a block of code when the condition in an
`if` expression is false.
`if` expression is false.\
For example:
```rust
@@ -38,7 +38,7 @@ if number < 5 {
## Booleans
The condition in an `if` expression must be of type `bool`, a **boolean**.
The condition in an `if` expression must be of type `bool`, a **boolean**.\
Booleans, just like integers, are a primitive type in Rust.
A boolean can have one of two values: `true` or `false`.
@@ -67,12 +67,12 @@ error[E0308]: mismatched types
```
This follows from Rust's philosophy around type coercion: there's no automatic conversion from non-boolean types to booleans.
Rust doesn't have the concept of **truthy** or **falsy** values, like JavaScript or Python.
Rust doesn't have the concept of **truthy** or **falsy** values, like JavaScript or Python.\
You have to be explicit about the condition you want to check.
### Comparison operators
It's quite common to use comparison operators to build conditions for `if` expressions.
It's quite common to use comparison operators to build conditions for `if` expressions.\
Here are the comparison operators available in Rust when working with integers:
- `==`: equal to
@@ -84,7 +84,7 @@ Here are the comparison operators available in Rust when working with integers:
## `if/else` is an expression
In Rust, `if` expressions are **expressions**, not statements: they return a value.
In Rust, `if` expressions are **expressions**, not statements: they return a value.\
That value can be assigned to a variable or used in other expressions. For example:
```rust
@@ -96,11 +96,10 @@ let message = if number < 5 {
};
```
In the example above, each branch of the `if` evaluates to a string literal,
which is then assigned to the `message` variable.
In the example above, each branch of the `if` evaluates to a string literal,
which is then assigned to the `message` variable.\
The only requirement is that both `if` branches return the same type.
## References
- The exercise for this section is located in `exercises/02_basic_calculator/03_if_else`
- The exercise for this section is located in `exercises/02_basic_calculator/03_if_else`