Macro ccase 

macro_rules! ccase {
    ($case:ident, $e:expr) => { ... };
    ($from:ident -> $to:ident, $e:expr) => { ... };
}

Convert an identifier into a case.

The macro can be used as follows.

use convert_case::ccase;

assert_eq!(ccase!(snake, "myVarName"), "my_var_name");
// equivalent to
// "myVarName".to_case(Case::Snake)

You can also specify a from case, or the case that determines how the input string is split into words.

use convert_case::ccase;

assert_eq!(ccase!(sentence -> snake, "Ice-cream sales"), "ice-cream_sales");
// equivalent to
// "Ice-cream sales".from_case(Case::Sentence).to_case(Case::Snake)