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_valueCode explanation
use std::env;: This imports theenvmodule from thestdlibrary, which provides functions for setting and getting environment variables.env::set_var("MY_VAR", "my_value");: This sets the environment variableMY_VARto the valuemy_value.env::var("MY_VAR").unwrap();: This retrieves the value of the environment variableMY_VAR. Theunwrap()function is used to convert theOptiontype returned byenv::varinto aString.
Helpful links
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