pub fn var<K: AsRef<OsStr>>(key: K) -> Result<String, VarError>Expand description
Fetches the environment variable key from the current process.
§Errors
Returns VarError::NotPresent if:
- The variable is not set.
- The variable’s name contains an equal sign or NUL (
'='or'\0').
Returns VarError::NotUnicode if the variable’s value is not valid
Unicode. If this is not desired, consider using var_os.
Use env! or option_env! instead if you want to check environment
variables at compile time.