# log_macro [<img alt="crates.io" src="https://img.shields.io/crates/v/log_macro.svg?style=for-the-badge&color=fc8d62&logo=rust" height="20">](https://crates.io/crates/log_macro)

> Macro to print variable(s) with values nicely (stripped from release builds)

## Install

```
cargo add log_macro
```

## Use

Add this to top of file:

```rust
#[macro_use]
extern crate log_macro;
```

Possible uses and outputs:

```rust
// print string only
log!("hello"); // -> hello

// print variable
let animals = vec!["cat", "dog"];
log!(animals); // -> animals: ["cat", "dog"]

// print multiple variables
let animals = vec!["cat", "dog"];
let fish = vec!["salmon", "tuna"];
log!(animals, fish);
// each variable logged on new line
// -> animals: ["cat", "dog"]
// -> fish: ["salmon", "tuna"]
```

Variables will be in green color to stand out.

## Implementation

Exported macro code is this:

```rust
#[macro_export]
macro_rules! log {
    // Single literal string case
    ( $val:expr $(,)? ) => {{
        #[cfg(debug_assertions)]
        {
            if ::std::stringify!($val).starts_with("\"") {
                // Remove quotes for string literals
                ::std::eprintln!("{}", ::std::stringify!($val).trim_matches('\"'));
            } else {
                // Print using a reference to avoid moving the value
                ::std::eprintln!("\x1B[32m{}\x1B[0m: {:?}", ::std::stringify!($val), &$val);
            }
        }
    }};

    // Multiple variables case
    ( $($val:expr),+ $(,)? ) => {{
        #[cfg(debug_assertions)]
        {
            $(
                $crate::log!($val);
            )+
        }
    }};
}
```

## Run

Will run the tests in [src/lib.rs](src/lib.rs).

```
cargo watch -q -- sh -c "tput reset && cargo test -q --lib"
```

## Contribute

The tasks to do are outlined in [existing issues](../../issues) and in [tasks below](#tasks) (sorted by priority).

If issue/idea you have is not there, [open new issue](../../issues/new/choose) or [start discussion](../../discussions).

Any PR with code/doc improvements is welcome. ✨

Join [Discord](https://discord.com/invite/TVafwaD23d) for more indepth discussions on this repo and [others](https://github.com/nikitavoloboev#src).

## Tasks

- fix docset for the macro export, [nothing is showing](https://docs.rs/log_macro/latest/log_macro/macro.log.html)
  - there are some errors present after running `cargo test --doc --package log_macro -- log --nocapture`. fix them
- fix the tests
  - currently they fail as I am not sure how to actually test that the logs are as they are
  - GPT says to try use [duct](https://crates.io/crates/duct) potentially but that gave some issues
- [add support for multiple values or different ways of formatting](https://www.reddit.com/r/rust/comments/15wd5u6/comment/jx074g9/?utm_source=share&utm_medium=web2x&context=3)
  - not sure what author meant, investigate
- [get the same level of utilities that Python’s formatted string literals have](https://www.reddit.com/r/rust/comments/15wd5u6/comment/jx109os/?utm_source=share&utm_medium=web2x&context=3)
  - `> print(f”operation: {2+1=}”)` -> `operation: 2+1=3`
- decide if macro should be stripped from release builds or not
  - currently it's stripped similar to `dbg!`
  - potentially provide another near identical macro to keep similar logs but also in release mode?

### ♥️

[Support on GitHub](https://github.com/sponsors/nikitavoloboev) or look into [other projects](https://nikiv.dev/projects).

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