When writing a computer program, we often want it to execute different actions for different scenarios and conditions.
In Rust, this is where the if
expression comes in. Let’s have a look at what the if
expression is.
The form of an if
expression is a condition, followed by a block of code; there can be an else expression with this block of code.
See the syntax below for a basic if
expression in Rust:
if expression {
/* block of code in case expression
is TRUE */
} else {
/* block of code in case expression
is FALSE */
}
Let’s consider a simple example where we have to determine which number is greater out of the integer variables a
and b
. The code snippet below illustrates how this can be done using an if
expression in Rust:
fn main() {let a = 50;let b = 20;if a > b {// condition is TRUEprintln!("a is greater than b")} else {// condition is FALSEprintln!("a is less than b")}}
The code above follows the process flow below:
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