Jan-Pieter,
Forward and back buttons are a good idea; I will work on them soon.
I have put out version 3.4.3 which addresses the other issues you
brought up.
1. Lev was being executed in the wrong locale. This is now fixed, but
Lev as shown will not get through dissect because dissect assumes that a
user-written modifier produces a verb. I don't see any way to fix that.
2. pow (or any other cover name that is defined tacitly) is now
supported as if you had written ^: .
3. The selection error in dissect '+: ^: 4 [6' is fixed.
4. Generally, you can click on any result to get an expansion or to
highlight the inputs that produced it. The exception is when the result
is a single cell and there is no further detail available. When this
happens, the program displays a tooltip telling you that.
Unfortunately, it removed the tooltip when you released the mouse, so if
you were a fast clicker you never saw it. I have forced the message to
linger on the screen for at least half a second; see if that makes
things clearer.
5. Now you can remove an expansion by clicking on the result that caused
the expansion to be created in the first place. This doesn't work for
$:, but it does for the rest: / ^: etc.
Thanks much for the suggestions. I expect that it will take quite a bit
of feedback to produce the best user interface.
Henry Rich
On 12/14/2014 11:42 AM, Jan-Pieter Jacobs wrote:
Henry,
congratulations with this tool it's really an excellent help for debugging
complex things, and explaining J phrases to beginners.
I ran into some errors though, when playing around with conjunctions:
Lev =: 2 : 'u'
1 Lev 2 Lev 3'
1
dissect '1 Lev 2 Lev 3'
value error
|value error: Lev
| exeobj=.1 (Lev)2
and
pow =: ^:
dissect '+: ^: 4 [6' NB. works as expected
dissect '+: pow 4 [ 6'
dissect error: internal result does not match the result from the J
session! Aborting.
y=
┌────┬┐
│┌──┐││
││96│││
│└──┘││
└────┴┘
With the first one (+: ^: 4 [6) it shows the window as expected, and also
the recursions when clicked on the final result, but clicking on any
intermediate result gives an error message.
For the Quicksort example you gave it does work though.
Just to let you know.
As I said, I really like dissect, but I'm having a bit of a hard time
navigating around. To me, it's not really clear what is clickable and why.
It would also be nice to have a way to undo expansions, or go to a previous
view (like a back button), especially when tracing around in something like
the Quicksort example.
Kind regards,
Jan-Pieter
2014-12-13 22:31 GMT+01:00 Henry Rich <[email protected]>:
Dissect, the 2-D sentence debugger, now supports all J primitives, in most
of their forms (it doesn't handle gerunds on partitioning modifiers or }).
It is an addon and is described at
http://www.jsoftware.com/jwiki/Vocabulary/Dissect
Dissect is especially useful if you are teaching J. Suppose a student
reads that +//.@(*/) does polynomial multiplication. How much fun is it
going to be to explain THAT? Just let em run
dissect '4 1 2 3 +//.@(*/) _1 4 0 2 6'
and they can happily click on individual numbers and see where they came
from.
Even if you're an expert you will want to use dissect if you have a
complicated sentence that is failing. For example:
]a =. (<0 1);<(<2 3 4);(1);<<5 6;7 8
+-----+-----------------------+
|+---+|+-------+-+-----------+|
||0 1|||+-----+|1|+---------+||
|+---+|||2 3 4|| ||+---+---+|||
| ||+-----+| |||5 6|7 8||||
| || | ||+---+---+|||
| || | |+---------+||
| |+-------+-+-----------+|
+-----+-----------------------+
a: ,L:1 a
|domain error
| a: ,L:1 a
You might not be one of the very few people, if indeed there are any, who
can see right off why this sentence failed. But if you run
dissect 'a: ,L:1 a'
or just use a PFkey set up to dissect the last line that failed, you will
immediately see the source of the problem. (The Wiki shows how to set up a
PFkey).
How about debugging recursions? Bring back some painful memories? Looking
at an error message like
'b c' =. 'a';5
>:`($:&.>)@.(0<L.) 1 2 3;<4 5;<<b;c
|domain error
| >:`($:&.>)@.(0<L.)1 2 3;<4 5;<<b;c
?
Run
dissect '>:`($:&.>)@.(0<L.) 1 2 3;<4 5;<<b;c'
and you'll see the results of all the recursions, with the failing one
exposed in detail; you can look through them one at a time if you like.
For fun, you can see quicksort (as described in the J Wiki) all at once
with
a =. 20 ? 50
dissect '(($:@(<#[) , (=#[) , $:@(>#[)) ({~ ?@#)) ^: (1<#) a'
Henry Rich
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