Command-line interface¶
Hy provides a handful of command-line programs for working with Hy code.
hy¶
hy is a command-line interface for Hy that in general imitates the program
python provided by CPython. For example, hy without arguments launches
the REPL if standard input is a TTY and runs the standard input
as a script otherwise, whereas hy foo.hy a b runs the Hy program
foo.hy with a and b as command-line arguments. See hy --help
for a complete list of options and Python's documentation for many details. Here are some Hy-specific details:
- --spy¶
Print equivalent Python code before executing each piece of Hy code in the REPL:
=> (+ 1 2) 1 + 2 ------------------------------ 3
- --repl-output-fn¶
Set the REPL output function. This can be the name of a Python builtin, most likely
repr, or a dotted name likefoo.bar.baz. In the latter case, Hy will attempt to import the named object with code like(import foo.bar [baz]).
hy2py¶
hy2py is a program to convert Hy source code into Python source code. Use hy2py --help for usage instructions. It can take its input from standard input, or from a file or module name provided as a command-line argument. In the case of a module name, the current working directory should be the parent directory of that module, and the output parameter (--output/-o) is required. When the output parameter is provided, the output will be written into the given folder or file. Otherwise, the result is written to standard output.
Warning
hy2pycan execute arbitrary code (via macros,eval-when-compile, etc.). Don't give it untrusted input.
hyc¶
hyc is a program to compile files of Hy code into Python bytecode. Use hyc --help for usage instructions. The generated bytecode files are named and placed according to the usual scheme of your Python executable, as indicated by importlib.util.cache_from_source().
Warning
hyccan execute arbitrary code (via macros,eval-when-compile, etc.). Don't give it untrusted input.