IRust

Cross Platform Rust Repl

You can try out IRust with no installation or setup (via Gitpod.io) by visiting https://gitpod.io/#https://github.com/sigmaSd/IRust

Keywords / Tips & Tricks

:help => print help, use :help full for the full version

: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. If no editor is specified then the one from the EDITOR environment variable is used (if set). 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: => 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

:dbg <expression> => Spawn lldb/gdb with the specified expression, example: :dbg fact(12), The debugger can be specified in the config file

:exit | :quit => Exit IRust immediately

$$ => Shell commands can be interpolated with rust code with '$$', for example: let a = $$ls -l$$;, this feature can be [en/dis]abled via the config file

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

You can use arrow keys to cycle through commands history

Keybindings

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

ctrl-o->**[+-]key** Start recording a macro and saved on the specified key, if ctrl-o is clicked again the recording is stopped

ctrl-p->key Play a macro saved on the specified key

ctrl-u Undo

ctrl-y Redo

ctrl-x Delete current line

Cli commands

--help prints help message

--reset-config reset IRust configuration to default

Configuration

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
  
  # select executor (Sync, Tokio, Asyncstd)
  executor = "Sync"
  evaluator = ["println!(\"{:?}\", {\n", "\n});"]
  compile_time = false
  main_result = "Unit"
  show_warnings = false
  edition = "E2021"
  debugger = "LLDB"
  shell_interpolate = true

Theme

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"
  symbol = "red"
  macro = "dark_yellow"
  literal = "yellow"
  lifetime = "dark_magenta"
  comment = "dark_grey"
  const = "dark_green"
  ident = "white"

Prelude

IRust automatically creates irust_prelude crate at xdg_data_dir/irust/irust_prelude, this crate is imported at startup, any changes to it (that are marked with pub) will be immediately reflected on the repl after saving.

Scripts

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.
Check out SCRIPTS.md for more info.

Book

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

Releases

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

Building

cargo b --release

FAQ

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.

Changelog