Hi Juan, I see that your new transcript is indeed much faster but is also not editable. I wonder if it would be possible to have the best of both worlds and arrange that, when active, the transcript is editable. For example, selecting the TranscriptWIndow could put it into a mode where the transcript's state was imported into a more conventional editable text morph, and then when the window was exited, reverted to the standard fast output mode. As you can infer I like having an editable transcript. I can do without it, because Squeak's slow transcript is indeed a PITA, but I'm not sure that speed need preclude editability. On Sat, May 9, 2015 at 10:17 AM, J. Vuletich (mail lists) < juanlists@jvuletich.org> wrote:
Hi Folks,
(below)
Quoting Ben Coman <btc@openinworld.com>:
On Sat, May 9, 2015 at 10:35 PM, Eliot Miranda <eliot.miranda@gmail.com>
wrote:
On Sat, May 9, 2015 at 7:09 AM, Ben Coman <btc@openinworld.com> wrote:
From my limited experience bug hunting, calling #changed: from a thread
other than the UI thread is a source of evil. There are too many assumptions throughout the system that the UI is single threaded. Can anyone advise me that is not a proper belief?
Then that implies that a Transcript implementation where #nextPut: direct calls #changed: is not appropriate for use with multi-threaded applications. In Pharo, #changed: is only called from #stepGlobal, which is called from doOneCycle:. (This came about as a last minute bug fix before Pharo 3 release and maybe could use some cleanup.
Separating the UI from Transcript into its own viewer might be a good idea, but actually it would not solve Stef's case since his code would still be running in the UI thread -- unless the viewer ran in another thread, which would have its own complexities.
I think the point about efficiency is significant. The following example... Time millisecondsToRun: [ 1000 timesRepeat: [ Transcript show: 'x' ] ] on Squeak 4.5 --> 12749ms on Pharo 50029 --> 2ms
This better performance helped me a lot trying to understand the high priority timerEventLoop being able to indiscriminately scatter Transcript tracing through that code. I believe its also probably beneficial for working with externally triggered semaphores and timing sensitive race conditions.
So we have two mutually exclusive cases: * better interactivity, poorer system performance * faster system performance, worse interactivity
Which of these is broken depends on your viewpoint.
Something that runs fast but is incorrect is still incorrect. The fact that the transcript doesn't output until a world step is possible is a bug. It forces programs that use the transcript to be rewritten in order to see transcript output.
As a point of comparison for correctness, for the following...
Transcript clear. [ $a asciiValue to: $z asciiValue do: [ :c | [ 1 to: 9 do: [ :i | Transcript show: c asCharacter printString , i printString , ' ' ] ] forkAt: 40 ]. ] forkAt: 41
Squeak 4.5 gives... $a1 $a2 $a3 $a4 $a5 $a6 $a7 $a8 $a9 $b1 $b2 $b3 $b4 $b5 $b5 $c1 $c2 $c3 $c4 $c5 $c6 $c7 $c8 $c9 $d1 $d2 $d3 $d4 $d5 $d6 $d7 $d8 $d9 $d9 $e2 $g2 $h2 $h2 $i2 $k2 $k2 $l2 $n2 $n2 $o2 $o2 $r2 $s2 $t2 $u2 $u2 $v2 $x2 $y2 $z2 $z2 $b7 $f3 $e3 $e3 $g3 $j3 $h3 $i3 $k3 $k3 $m3 $n3 $p3 $p3 $q3 $o3 $s3 $t3 $t3 $u3 $v3 $x3 $y3 $z3 $b8 $f4 $e4 $e4 $g4 $h4 $i4 $k4 $l4 $m4 $m4 $n4 $r4 $q4 $o4 $o4 $s4 $w4 $u4 $u4 $v4 $y4 $y4 $z4 $z4 $f5 $j5 $j5 $g5 $i5 $k5 $l5 $l5 $m5 $m5 $n5 $q5 $o5 $s5 $s5 $t5 $u5 $u5 $x5 $y5 $z5 $f6 $f6 $h6 $h6 $g6 $g6 $k6 $p6 $m6 $r6 $r6 $n6 $o6 $s6 $s6 $w6 $u6 $x6 $x6 $e7 $f7 $j7 $h7 $h7 $i7 $l7 $l7 $k7 $m7 $m7 $q7 $n7 $n7 $o7 $t7 $w7 $w7 $u7 $v7 $x7 $z7 $z7 $e8 $e8 $h8 $g8 $i8 $i8 $l8 $k8 $k8 $m8 $q8 $n8 $n8 $s8 $t8 $w8 $y8 $y8 $u8 $x8 $z8 $f9 $f9 $e9 $h9 $h9 $g9 $p9 $p9 $k9 $r9 $r9 $m9 $n9 $n9 $o9 $t9 $t9 $w9 $v9 $u9 $u9 $z9 $x9
Pharo 50041 gives... $a1 $a2 $a3 $a4 $a5 $a6 $a7 $a8 $a9 $b1 $b2 $b3 $b4 $b5 $b6 $b7 $b8 $b9 $c1 $c2 $c3 $c4 $c5 $c6 $c7 $c8 $c9 $d1 $d2 $d3 $d4 $d5 $d6 $d7 $d8 $d9 $e1 $e2 $e3 $e4 $e5 $e6 $e7 $e8 $e9 $f1 $f2 $f3 $f4 $f5 $f6 $f7 $f8 $f9 $g1 $g2 $g3 $g4 $g5 $g6 $g7 $g8 $g9 $h1 $h2 $h3 $h4 $h5 $h6 $h7 $h8 $h9 $i1 $i2 $i3 $i4 $i5 $i6 $i7 $i8 $i9 $j1 $j2 $j3 $j4 $j5 $j6 $j7 $j8 $j9 $k1 $k2 $k3 $k4 $k5 $k6 $k7 $k8 $k9 $l1 $l2 $l3 $l4 $l5 $l6 $l7 $l8 $l9 $m1 $m2 $m3 $m4 $m5 $m6 $m7 $m8 $m9 $n1 $n2 $n3 $n4 $n5 $n6 $n7 $n8 $n9 $o1 $o2 $o3 $o4 $o5 $o6 $o7 $o8 $o9 $p1 $p2 $p3 $p4 $p5 $p6 $p7 $p8 $p9 $q1 $q2 $q3 $q4 $q5 $q6 $q7 $q8 $q9 $r1 $r2 $r3 $r4 $r5 $r6 $r7 $r8 $r9 $s1 $s2 $s3 $s4 $s5 $s6 $s7 $s8 $s9 $t1 $t2 $t3 $t4 $t5 $t6 $t7 $t8 $t9 $u1 $u2 $u3 $u4 $u5 $u6 $u7 $u8 $u9 $v1 $v2 $v3 $v4 $v5 $v6 $v7 $v8 $v9 $w1 $w2 $w3 $w4 $w5 $w6 $w7 $w8 $w9 $x1 $x2 $x3 $x4 $x5 $x6 $x7 $x8 $x9 $y1 $y2 $y3 $y4 $y5 $y6 $y7 $y8 $y9 $z1 $z2 $z3 $z4 $z5 $z6 $z7 $z8 $z9
(start your comparison at $b5)
So in one axis Pharo has improved Transcript, but we didn't notice the significance of the use case we lost.
cheers -ben
Please take a good look at Cuis' Transcript and consider using it.
By default, the display is updated immediately, but without calling Morphic, it can even work with no UI framework at all. It does updates faster than Squeak or Visualworks:
Time millisecondsToRun: [ 1000 timesRepeat: [ Transcript show: 'x' ] ]. 763.
But if you want minimum overhead without immediate feedback:
Time millisecondsToRun: [ Transcript showOnDisplay: false. 1000 timesRepeat: [ Transcript show: 'x' ]. Transcript showOnDisplay: true ]. 1. "As fast as Pharo"
It is also thread safe, and for Ben's example:
Transcript clear. [ $a asciiValue to: $z asciiValue do: [ :c | [ 1 to: 9 do: [ :i | Transcript show: c asCharacter printString , i printString , ' ' ] ] forkAt: 40 ]. ] forkAt: 41
it gives the same result as Pharo.
The fact that the updates are not bound to Morphic also means that it is possible to do #show: deep in Morphic logic, without causing infinite loops or recursions, and get immediate feedback. It has proved to be a useful aid in debugging Morphic code.
Cheers, Juan Vuletich
-- best, Eliot