Navigation?

[conal]

Does navigation work in the latest HERMIT? The commands down, left, and right aren't recognized. I found navigate, but when I use the down, left, or right keys in navigation mode, I get error messages like the following.

User error, unrecognized HERMIT command: "down"

Moreover, I like to run Hermit (and most things I do) inside Emacs, where those keys don't make it to the HERMIT process.

[andygill]

I believe that they are replaced by named commands, specific to the node at hand. One thing I will be working on as a matter of priority is documenting things (like this). I'll file a ticket about documentation.

[conal]

Great. Thanks. Meanwhile, I'm perusing the results of help Navigation.

[ecaustin]

I've been out of the loop for a bit, but last I recall the only navigation commands that we still supported were up and top.

I believe even those were under discussion for removal, or at least reimplementation.

[xich]

Yep, help Navigation should list things.

The directions have all been replaced by "crumbs". A crumb is a pair of parent and child (app-fun is the crumb which moves from an application node to it's function child. app-arg is the crumb that moves from application node to it's argument child.) A path is a list of crumbs. You can type in paths with Haskell list syntax. For instance, [lam-body, app-fun] should move you from (\y -> f y) to f.

There are other more powerful navigation commands like lams-body which just repeats lam-body until failure. Also binding-of, rhs-of, occurrence-of, and top.

[xich]

(The justification for crumbs is in section 4.2.2 of my dissertation.)

[conal]

Thanks. I just grabbed a copy.

On Sun, Jan 3, 2016 at 9:16 PM, Andrew Farmer [email protected]
wrote:

(The justification for crumbs is in section 4.2.2 of my dissertation.)

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[conal]

Is the "navigation" command/mode obsolete?

On Sun, Jan 3, 2016 at 9:13 PM, Evan Austin [email protected]
wrote:

I've been out of the loop for a bit, but last I recall the only navigation
commands that we still supported were up and top.

I believe even those were under discussion for removal, or at least
reimplementation.

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#154 (comment).

[conal]

Nice! Thanks for the tips.

On Sun, Jan 3, 2016 at 9:15 PM, Andrew Farmer [email protected]
wrote:

Yep, help Navigation should list things.

The directions have all been replaced by "crumbs". A crumb is a pair of
parent and child (app-fun is the crumb which moves from an application
node to it's function child. app-arg is the crumb that moves from
application node to it's argument child.) A path is a list of crumbs. You
can type in paths with Haskell list syntax. For instance, [lam-body,
app-fun] should move you from (\y -> f y) to f.

There are other more powerful navigation commands like lams-body which
just repeats lam-body until failure. Also 'binding-of', rhs-of,
occurrence-of, and top.

—
Reply to this email directly or view it on GitHub
#154 (comment).