153 releases (44 stable)

new 1.27.0 Sep 22, 2021
1.24.0 Aug 1, 2021
1.22.2 Jul 14, 2021
1.2.8 Mar 31, 2021
0.6.10 Jul 31, 2019

#18 in Development tools

Download history 189/week @ 2021-06-06 79/week @ 2021-06-13 35/week @ 2021-06-20 92/week @ 2021-06-27 63/week @ 2021-07-04 58/week @ 2021-07-11 172/week @ 2021-07-18 177/week @ 2021-07-25 373/week @ 2021-08-01 48/week @ 2021-08-08 212/week @ 2021-08-15 19/week @ 2021-08-22 30/week @ 2021-08-29 23/week @ 2021-09-05 59/week @ 2021-09-12 89/week @ 2021-09-19

463 downloads per month

MIT license



Cross Platform Rust Repl

Keywords / Tips & Tricks

:help => print help

:reset => reset repl

:show => show repl current code (optionally depends on rustfmt to format output)

:add <dep_list> => add dependencies (requires cargo-edit) also it accepts most cargo-edit arguments

:type <expression> => shows the expression type, example :type vec!(5)

:time <expression> => return the amount of time the expression took to execute. example: :time 5+4 :time my_fun(arg1,arg2)

:time_release <expression> => same as time command but with release mode

:load => load a rust file into the repl

:reload => reload the last specified file

:pop => remove last repl code line

:del <line_num> => remove a specific line from repl code (line count starts at 1 from the first expression statement)

:edit <editor> => edit internal buffer using an external editor, example: :edit micro, Note some gui terminal requires using :sync command after the edit (vscode)

:sync sync the changes written after using :edit with a gui editor (vscode) to the repl

:cd => change current working directory

:color <key> <value> => change token highlight color at runtime, for the token list and value representation check the Theme section, exp: :color function red :color macro #ff12ab :color reset

:toolchain <value> => switch between toolchains, supported value are: stable, beta, nighty, default

:check_statements true/false => If its set to true, irust will check each statemnt (input that ends with ;) with cargo_check before inserting it to the repl

:bench => run cargo bench

:asm <function> => shows assembly of the specified function, note that the function needs to be public, and there has to be no free standing statements/expressions (requires cargo-asm)

:executor <executor> => set the executor to be used by IRust, available options are: sync tokio async_std, by using an async executor, await becomes usable with no other modifications (requires cargo-edit for async executors)

:evaluator <evaluator>> => set the evaluator statement, exmaple: :evaluator println!("{}",{$$}) the $$ will be replaced by IRust by the input code (the default evaluator uses debug formatting). To reset the evaluator to default you can use :evaluator reset

:scripts: => only supported by script v3/v4, if invoked with no arguments it prints a list of detected scripts, if invoked with on argument it print that script info if it exits, if invoked with 2 arguments, it tries to activate/deactivate a script, example: :scripts Vim deactivate

:compile_time <on/off> => if set to on, IRust will print compiling time on each input, compile time includes rustc compiling + some IRust code (should be marginal)

:main_result <value> => Change main result type, available options are Unit and Result (which is Result<(), Box<dyn std::error::Error>>), Using Result as type allows to use ? in the repl without any boilerplate

:exit | :quit => Exit IRust immediately

:: => run a shell command, example ::ls

You can use arrow keys to cycle through commands history


ctrl-l clear screen

ctrl-c clear line

ctrl-d exit if buffer is empty

ctrl-z [unix only] send IRust to the background

ctrl-r search history, hitting ctrl-r again continues searching the history backward, hitting ctrl-s searches the history forward

ctrl-left/right jump through words

HOME/END go to line start / line end

Tab/ShiftTab cycle through auto-completion suggestions (requires racer)

Alt-Enter add line break

ctrl-e force evaluation

Cli commands

--help prints help message

--reset-config reset IRust configuration to default


IRust config file is located in:

Linux: /home/$USER/.config/irust/config

Win: C:\Users\$USER\AppData\Roaming/irust/config

Mac: /Users/$USER/Library/Preferences/irust/config

default config:

  # history
  add_irust_cmd_to_history = true
  add_shell_cmd_to_history = false

  # colors
  ok_color = "Blue"
  eval_color = "White"
  irust_color = "DarkBlue"
  irust_warn_color = "Cyan"
  out_color = "Red"
  shell_color = "DarkYellow"
  err_color = "DarkRed"
  input_color = "Green"
  insert_color = "White"
  welcome_msg = ""
  welcome_color = "DarkBlue"

  # racer
  racer_inline_suggestion_color = "Cyan"
  racer_suggestions_table_color = "Green"
  racer_selected_suggestion_color = "DarkRed"
  racer_max_suggestions = 5
  enable_racer = true

  # other
  first_irust_run = false
  toolchain = "stable"
  check_statements = true
  auto_insert_semicolon = true
  // use last output by replacing the specified marker
  replace_marker = "$out"
  replace_output_with_marker = false
  # modify input prmopt
  input_prompt = "In: "
  output_prompt = "Out: "
  # activate scripting feature
  activate_scripting = false
  activate_scripting2 = false
  activate_scripting3 = false
  activate_scripting4 = false
  # select executor (Sync, Tokio, Asyncstd)
  executor = "Sync"
  evaluator = ["println!(\"{:?}\", {\n", "\n});"]
  compile_time = false
  main_result = "Unit"


Since release 0.8.9 IRust can now parse a theme file located on $config_dir/irust/theme and use it for the highlighting colors.

Colors can be specified as names ("red") or as hex representation ("#ff12ab").

Default theme file:

  keyword = "magenta"
  keyword2 = "dark_red"
  function = "blue"
  type = "cyan"
  number = "dark_yellow"
  symbol = "red"
  macro = "dark_yellow"
  string_literal = "yellow"
  character = "green"
  lifetime = "dark_magenta"
  comment = "dark_grey"
  const = "dark_green"
  x = "white"


IRust supports scripting, all over the code base there are hooks that scripts can react to and usually answer back to IRust with a command.
IRust supports different versions of scripting, the latest version is the most supported one.
The older versions are kept for backward compatibility reasons but mainly because scirpting is currently on developement and I haven't decided which method is the best yet.
Check out SCRIPTS.md for more info.


The IRust Book is intended to document a couple of tips and tricks https://sigmasd.github.io/irust_book


Automatic releases by github actions are uploaded here https://github.com/sigmaSd/irust/releases


cargo b --release


1- Why is autocompletion not working

-> you need racer installed and configured correctly
    cargo +nightly install racer
    rustup component add rust-src

2- Racer fails to build

You can try rustup update --force https://github.com/racer-rust/racer/issues/1141

3- I want to hack on irust but dbg! overlaps with the output!!

Personaly I do this:

  • Run 2 terminals side by side
  • run tty in the first which should output something like /dev/pts/4
  • run cargo r 2>/dev/pts4 in the second

Now the dbg! statements are printed on the second terminal and the output in the first terminal is not messed up.



~67K SLoC