Node.js REPL with lodash
Sometimes we use the Node.js REPL interface to experiment with code. Wouldn’t it be great to have that interface with lodash required by default?
$ npm install -g n_
$ n_
n_ >
lodash is now attached to the REPL context as _
, so just use it:
n_ > _.compact([0, 1, false, 2, '', 3]);
[ 1, 2, 3 ]
n_ >
It is possible to use lodash’s functional programming variant lodash/fp
:
$ n_ --fp
n_ > _.map(function(v) { return v * 2; }, [1, 2, 3]);
[ 2, 4, 6 ]
n_ >
It is possible to enable strict mode in Node.js >= 4.x:
$ n_ --use_strict
n_ >
Or alternatively:
$ NODE_REPL_MODE=strict n_
n_ >
The _
character is special in the Node REPL (see nodejs.org/api/repl.html).
In node versions < 6.x n_ redirects this special variable to $
per default, but you can set your own using the environment variable SPECIAL_VAR
like this:
$ SPECIAL_VAR=my_var n_
n_ > 123
123
n_ > my_var
123
n_ >
Also note that in node < 6.x using the command .clear
you clear the context lodash is bound to.
The behavior of assigning _
to the last evaluated expression is disabled, since lodash is already assigned to _
.
n_ stores its session history under ~/.n_repl_history
.
Enjoy!