rustWhat is an environment variable in Rust?
An environment variable in Rust is a global variable that can be accessed from any part of the program. It is used to store information that can be used by multiple parts of the program. Environment variables are set using the std::env::set_var
function.
Example code
use std::env;
fn main() {
env::set_var("MY_VAR", "my_value");
println!("MY_VAR is set to: {}", env::var("MY_VAR").unwrap());
}
Output example
MY_VAR is set to: my_value
Code explanation
use std::env;
: This imports theenv
module from thestd
library, which provides functions for setting and getting environment variables.env::set_var("MY_VAR", "my_value");
: This sets the environment variableMY_VAR
to the valuemy_value
.env::var("MY_VAR").unwrap();
: This retrieves the value of the environment variableMY_VAR
. Theunwrap()
function is used to convert theOption
type returned byenv::var
into aString
.
Helpful links
Related
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- How do I zip variables in Rust?
- How do I write a variable to a file in Rust?
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- How can I use a mutex as a global variable in Rust?
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- How can I use a hashmap as a global variable in Rust?
- How do I declare a variable outside a function in Rust?
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See more codes...