Rank CLI

rank runs a .ra source file. With no file argument it opens the terminal REPL.

Requires Node.js 22.12 or newer, Python, and a C++20 build toolchain.

npm install -g @arrrank/cli
rank

rank program.ra --limit 10
rank test path/to/program_test.ra
rank test path/to/directory

rank test runs test files ending in _test.ra.

In the REPL, Enter submits the bottom prompt. Up returns to earlier code for editing; Down or Esc returns to the prompt. Enter inside earlier code inserts a line. Ctrl-R submits the prompt from anywhere in the document. Submitting the prompt reruns the document from its first edit and stops at the first error, with the cursor ready to correct it. Newly submitted code stays in the document even when an earlier instruction fails. An empty Enter runs pending instructions without adding a line; when everything has run, it adds a blank line.

Gray circles mark pending instructions, yellow marks the current run, green marks success and red marks an error. Rerunning replaces the previous output. Long expressions are formatted to 40 columns with parentheses when a safe break exists. Terminal wrapping also fits the display to the window width.

During execution the footer shows elapsed time. Ctrl-C stops the current cell and returns to rank>; queued cells wait. The stopped cell keeps its source and an interruption message, including the source location when available. Select that cell and press Ctrl-R to retry it. Earlier bindings remain available. Cancellation runs finally blocks but does not undo mutations, consumed input, or file writes. It also covers lazy evaluation during result previews and full. The terminal runs separately from the interpreter; cancellation is checked in Rank loops, number calculations, sequence and array materialization, sorting, statistics, matrix operations, graph traversal and table processing. Generated tensor kernels also check for cancellation in interactive mode. File execution and piped input do not start a worker or poll a cancellation signal. A blocking native operation without a checkpoint must return before cancellation can take effect.

Tab completes and cycles matches in one footer. Ctrl-Z/Ctrl-Y undo and redo edits; Ctrl-Q exits. Type help for the other keys and commands, save FILE to save the source, or load FILE to open source in the session. Loading replaces the current document and clears interpreter state. Unsaved code can be saved before replacement, or the load can be cancelled. The new code stays pending; press Enter at rank> or Ctrl-R to run it. The footer shows the file name and saved / unsaved. Ctrl-S saves to the last loaded or saved file, or asks for a name for a new program. Saving includes any unsubmitted source without running it. Exiting with unsaved changes offers to save, discard changes, or cancel with Esc.

See REPL input for execution and input details.

Stored native sources in the REPL keep their read position. After G = primes and G till 100 sum, inspecting G starts at 101. Previews do not consume values; H = G shares the cursor, while H = primes starts a fresh stream. Editing a consuming line restores the position left by its preceding lines. Normal file execution retains repeatable native sources. See sequence previews.