Macro cdbg

macro_rules! cdbg {
    (
     // shows no location (pretty-print)                            cdbg![# x];
     # $v:expr $(,)?) => { ... };
    (# $($v:expr),+ $(,)?) => { ... };
    (
     // shows no location                                           cdbg![x];
     //                                                             cdbg![@ x];
     $(@)? $v:expr $(,)?) => { ... };
    ($($v:expr),+ $(,)?) => { ... };
    (

     // shows the last $n location components                       cdbg![1@ x];
     // ($n=0 no location, $n=1 just the filename)
     $n:literal @ $v:expr $(,)?) => { ... };
    ($n:literal @ $($v:expr),+ $(,)?) => { ... };
    ($n:literal @) => { ... };
    (// (pretty-print)                                              cdbg![1# x];
     $n:literal # $v:expr $(,)?) => { ... };
    ($n:literal # $($v:expr),+ $(,)?) => { ... };
    ($n:literal #) => { ... };
    (

     // shows the full path location                                cdbg![f@ x];
     f @ $v:expr $(,)?) => { ... };
    (f @ $($v:expr),+ $(,)?) => { ... };
    (f @) => { ... };
    (// (pretty-print) (equivalent to `dbg!`)                       cdbg![f # x];
     f # $v:expr $(,)?) => { ... };
    (f # $($v:expr),+ $(,)?) => { ... };
    (f #) => { ... };
    (
     // shows the full path location in a separate line             cdbg![fln@ x];
     fln @ $v:expr $(,)?) => { ... };
    (fln @ $($v:expr),+ $(,)?) => { ... };
    (fln @) => { ... };
    (// (pretty-print)                                              cdbg![fln # x];
     fln # $v:expr $(,)?) => { ... };
    (fln # $($v:expr),+ $(,)?) => { ... };
    (fln #) => { ... };
    () => { ... };
}

Available on crate feature std only.

customizable dbg! macro.

• By default uses {:?} instead of {:#?} for formatting.
• By default doesn’t show the location (file, line and column).
• It can show the $n last components, instead of the full path.

Examples

let a = vec![1, 2, 3];

let _ = cdbg![&a];
let _ = cdbg![@ &a];
let _ = cdbg![0@ &a];
//      ^-- prints: &a = [1, 2, 3]
let _ = cdbg![1@ &a];
//      ^-- prints: [main.rs:6:10] &a = [1, 2, 3]
let _ = cdbg![2@ &a];
//      ^-- prints: [src/main.rs:8:10] &a = [1, 2, 3]
let _ = cdbg![f@ &a];
//      ^-- prints: [/full/path/.../src/main.rs:10:9] &a = [1, 2, 3]
let _ = cdbg![fln@ &a];
//      ^-- prints: [/full/path/.../src/main.rs:12:9]
//                  &a = [1, 2, 3]

// use `#` for pretty-printing:
let _ = cdbg![# &a];
let _ = cdbg![0# &a];    // same as cdbg![# &a]
let _ = cdbg![1# &a];
let _ = cdbg![f # &a];   // same as `dbg!` macro (notice the required whitespace)
let _ = cdbg![fln # &a]; // same as before, but separates the path in a new line