lexdrill

The lexdrill gem installs a drill command that prints a vocabulary word or phrase on demand, tracking how often each one has been shown.

Installation

gem install lexdrill

drill: command not found after install?

This happens when the gem's executable directory isn't on your PATH — common with a plain system Ruby (no rbenv/rvm). Fix it in one step:

bash

echo "export PATH=\"$(ruby -e 'puts Gem.bindir'):\$PATH\"" >> ~/.bashrc
source ~/.bashrc

zsh

echo "export PATH=\"$(ruby -e 'puts Gem.bindir'):\$PATH\"" >> ~/.zshrc
source ~/.zshrc

Using an rbenv-managed Ruby? Run rbenv rehash instead. Using rvm? You shouldn't hit this — rvm keeps gem executable directories on PATH automatically.

Usage

Create a .drill.txt file — one word or phrase per line — in your home directory, or in a specific project directory to give that project its own list:

apple
banana
cherry

If you don't create one, drill next seeds ~/.drill.txt with a default starter list (a set of NLP presuppositions) the first time it runs, so there's always something to drill.

Run drill next to print the current word and advance to the next one. There are two output styles (drill format simple|full, simple is the default):

simple — the drill sign (always blue), a space, then the word (in a separately-picked random color), all on one line:

⟳ apple

full — counter/total⟳[loop_start-loop_end] on one line, the word on the next, in a randomly-picked color:

1/6⟳[1-3]
apple

(word 1 of 6 total; currently in the loop spanning words 1-3)

Shell integration (one-time setup)

Add one line to your shell's rc file so the current word prints automatically before each prompt. This is a one-time step — the line stays in your rc file and takes effect in every new shell session from then on; you never need to run it again by hand.

Add it near the end of the file, after anything that sets up your PATH (rvm/rbenv init, Homebrew, etc.) — otherwise the shell may not know where drill lives yet when this line runs. Guarding it with command -v also means it never errors, even on a machine/session where drill isn't on PATH for some reason.

zsh — add to ~/.zshrc:

if command -v drill >/dev/null 2>&1; then
  eval "$(drill hook zsh)"
fi

bash — add to ~/.bashrc:

if command -v drill >/dev/null 2>&1; then
  eval "$(drill hook bash)"
fi

Then open a new shell (or source ~/.zshrc / source ~/.bashrc) to pick it up.

Hook not firing in new terminal windows/tabs (rvm users)?

Run drill inspect first — if it shows Toggle: enabled and a valid words file, the tool itself is fine and the problem is that the hook function never got registered in that session.

A common cause with rvm: rvm's installer sometimes puts its actual PATH-loading line ([[ -s "$HOME/.rvm/scripts/rvm" ]] && source "$HOME/.rvm/scripts/rvm") in ~/.zlogin (zsh) or ~/.bash_profile (bash). Those files only run for login shells — but many terminal emulators (e.g. kitty) open new windows/tabs as non-login interactive shells, which only source ~/.zshrc/~/.bashrc. So rvm's gemset bin/ directory (where drill lives) never makes it onto PATH in those sessions, even though everything looks correctly configured.

Fix: move that line into ~/.zshrc / ~/.bashrc (before the drill hook block above, so it runs first) instead of relying on it only being in ~/.zlogin / ~/.bash_profile. It's safe to leave it in both places.

Word only shows once per session, then stops (bash)

The bash hook works by appending a $(drill_precmd) command substitution to PS1, which bash re-evaluates on every prompt render — this is deliberate, since some environments (notably Google Cloud Shell's bashrc.google) snapshot and unconditionally overwrite PROMPT_COMMAND after your .bashrc runs, silently dropping anything hooked in that way. If you installed an older version of the hook and see the word print exactly once and never again, re-run drill hook bash and update the line in your .bashrc to the current snippet.

Rhythm (beat)

By default next just advances one word at a time. You can instead have it repeat loops of consecutive words — e.g. a loop of 3 words shown twice each before moving on:

drill beat 3 2     # loop size 3, repeat each loop 2 times

drill beat none turns it back off (plain word-by-word again). This is a global setting — it applies everywhere, independent of which project's .drill.txt is currently active.

There are also named shortcuts for common loop sizes, one word/phrase apart:

Loop size	Alias
2	polka
3	waltz
4	rock
5	jazz
6	jiga
7	balkan
8	samba

drill waltz 16 is shorthand for drill beat 3 16. Repetitions default to 8 if you leave them off — drill jazz alone is drill beat 5 8, and drill beat 4 alone is drill beat 4 8.

Commands

Command	What it does
drill next	Print the current word and advance
drill start / drill stop	Pause/resume the automatic per-prompt hook (doesn't affect manual next)
drill inspect	Show the active .drill.txt/.drill.counter paths, word count, counter value, toggle, and beat state
`drill hook zsh\	bash`	Print the shell integration snippet (used above)
drill beat <2-8> <repetitions> / drill beat none	Set or disable the rhythm
`drill polka\	waltz\	rock\	jazz\	jiga\	balkan\	samba `	Shorthand for a fixed loop size (see table above)
`drill format simple\	full`	Set the output style (simple is the default)