Re: Pesky java interop bug with 0xFFFFFFF error in BuferredReader
This is embarassing. ;-) Thanks -- You received this message because you are subscribed to the Google Groups "Clojure" group. To post to this group, send email to clojure@googlegroups.com Note that posts from new members are moderated - please be patient with your first post. To unsubscribe from this group, send email to clojure+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/clojure?hl=en --- You received this message because you are subscribed to the Google Groups "Clojure" group. To unsubscribe from this group and stop receiving emails from it, send an email to clojure+unsubscr...@googlegroups.com. To view this discussion on the web visit https://groups.google.com/d/msgid/clojure/3a4fb35a-a282-4762-bf08-4f891447b7b9n%40googlegroups.com.
Re: Pesky java interop bug with 0xFFFFFFF error in BuferredReader
Hank, Your last version does not work because your `if` condition is wrong, your code stops on the first read ;) Laurent Le lundi 27 décembre 2021 à 21:34:05 UTC+1, hank@gmail.com a écrit : > Ooops my bad, there's a typo in '(.toString sb1)' which sould be 'sb'. > It doesn't change anything, it still won't work, only Laurent's version > works. > > user> (defn pt%% [file] > > (let [afr (FileReader. file) > bfr (BufferedReader. afr)] >(loop [x (.read bfr) > sb (StringBuilder.)] > (if (not (= x -1)) > (.toString sb) > (recur (.append sb (char x)) (.read bfr)) > > #'user/pt%% > user> (pt%% ribs) > "" > > Which makes no sense to me... > -- Hank > > -- You received this message because you are subscribed to the Google Groups "Clojure" group. To post to this group, send email to clojure@googlegroups.com Note that posts from new members are moderated - please be patient with your first post. To unsubscribe from this group, send email to clojure+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/clojure?hl=en --- You received this message because you are subscribed to the Google Groups "Clojure" group. To unsubscribe from this group and stop receiving emails from it, send an email to clojure+unsubscr...@googlegroups.com. To view this discussion on the web visit https://groups.google.com/d/msgid/clojure/9252a765-a5ff-46d9-8c49-b9affb9d2651n%40googlegroups.com.
Re: Pesky java interop bug with 0xFFFFFFF error in BuferredReader
Ooops my bad, there's a typo in '(.toString sb1)' which sould be 'sb'. It doesn't change anything, it still won't work, only Laurent's version works. user> (defn pt%% [file] (let [afr (FileReader. file) bfr (BufferedReader. afr)] (loop [x (.read bfr) sb (StringBuilder.)] (if (not (= x -1)) (.toString sb) (recur (.append sb (char x)) (.read bfr)) #'user/pt%% user> (pt%% ribs) "" Which makes no sense to me... -- Hank -- You received this message because you are subscribed to the Google Groups "Clojure" group. To post to this group, send email to clojure@googlegroups.com Note that posts from new members are moderated - please be patient with your first post. To unsubscribe from this group, send email to clojure+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/clojure?hl=en --- You received this message because you are subscribed to the Google Groups "Clojure" group. To unsubscribe from this group and stop receiving emails from it, send an email to clojure+unsubscr...@googlegroups.com. To view this discussion on the web visit https://groups.google.com/d/msgid/clojure/310d27b9-1f6e-4017-9465-14ee8c7a4e15n%40googlegroups.com.
Re: Pesky java interop bug with 0xFFFFFFF error in BuferredReader
Hi -- Thanks so much, Laurent! I was actually kind of close (you told me not to peep, so I didn't hehe). (defn pt30 [file] (def ^:dynamic *asb* (StringBuilder.)) (let [afr (FileReader. file) bfr (BufferedReader. afr)] (loop [x (.read bfr) *asb* (StringBuilder.)] (when (not (= x -1)) (recur (.read bfr) (.append *asb* (java.lang.Character/toChars x))) with (def ribs "/path/to/ribs.txt") which looks similar. But, for some reason, the *asb* variable didn't populate with rib advertisements: user> (pt30 ribs) nil user> *asb* #object[java.lang.StringBuilder 0x29f4eb0c ""] When I convert this practically to the same you did, user> (defn pt34 [file] (let [afr (FileReader. file) bfr (BufferedReader. afr)] (loop [x (.read bfr) sb (StringBuilder.)] (if (not (= x -1)) (.toString sb1) (recur (.read bfr) (.append sb (char x))) #'user/pt34 user> (pt34 ribs) "" I still get no beef (err, ribs). Doesn't print anything either. Weird. Just weird. -- Hank -- You received this message because you are subscribed to the Google Groups "Clojure" group. To post to this group, send email to clojure@googlegroups.com Note that posts from new members are moderated - please be patient with your first post. To unsubscribe from this group, send email to clojure+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/clojure?hl=en --- You received this message because you are subscribed to the Google Groups "Clojure" group. To unsubscribe from this group and stop receiving emails from it, send an email to clojure+unsubscr...@googlegroups.com. To view this discussion on the web visit https://groups.google.com/d/msgid/clojure/3c1312f9-619b-4056-a54d-d880fcf80cf4n%40googlegroups.com.
Re: Pesky java interop bug with 0xFFFFFFF error in BuferredReader
Hank,
Just a message to give you the solution [spoiler alert]
Don't read it, if you still want to search :)
SPOILER
SPOILER
;; ugly version using the fact that java objects are mutable in place
(defn ugly-read-chars-one-by-one
[reader]
(let [sb (StringBuilder.)]
(loop []
(let [v (.read reader)]
(if (neg? v)
(.toString sb)
(do (.append sb (char v))
(recur)))
;; "better" version using loop bindings
(defn read-chars-one-by-one
[reader]
(loop [sb (StringBuilder.)
v (.read reader)]
(if (neg? v)
(.toString sb)
(recur (.append sb (char v))
(.read reader)
;; usage
(require '[clojure.java.io :as io])
(with-open [rdr (io/reader "some-file.txt")]
(read-chars-one-by-one rdr))
Regards,
Laurent
Le dimanche 26 décembre 2021 à 18:12:56 UTC+1, hank@gmail.com a écrit :
> Hi --
> Thanks for taking the time to help me.
> As far as I understand the examples, loop has this template:
>
> loop [binding]
> (condition
> (statement)
> (recur (binding)))
> And in 'recur' the loop is re-executed with new bindings.
>
> There was indeed an issue with the 'recur' outside 'when'. Thanks for
> pointing that out.
> I corrected that in the version below.
>
> I also changed to a smaller file (UTF-8 encoded in Linux), called
> 'ribs.txt', with the following content:
>
> source/txt on master [!?]
> ❯ cat ribs.txt
> Try my delicious pork-chop ribs!
>
> source/txt on master [!?]
> ❯ cat ribs.hexdump
> : 54 72 79 20 6d 79 20 64 65 6c 69 63 69 6f 75 73 Try my delicious
> 0010: 20 70 6f 72 6b 2d 63 68 6f 70 20 72 69 62 73 21 pork-chop ribs!
> 0020: 0a .
>
>
> (defn pt8 [file]
>(let [afr (FileReader. file); instances of FileReader, BufferedReader,
> StringBuffer
> bfr (BufferedReader. afr)
> ct (StringBuilder.)
> this-list (list afr bfr ct)]
> ; (apply println this-list)
> ; put recur INSIDE THE WHEN
> (loop [val (.read bfr)]
>(when (not (= val -1))
> (.append ct (Character/toChars (.read bfr)))
>(recur [val (.read bfr)])))
> ; when finished...
> (.toString ct)))
>
> I think this fixed the 'recur', because it does rebinding to a new call to
> "read()".
> However, the errors remains.
>
> user> (pt8 ribs)
> Execution error (IllegalArgumentException) at java.lang.Character/toChars
> (Character.java:8572).
> Not a valid Unicode code point: 0x
>
> The file used is sufficiently small so that we can walk the bytes using
> jshell:
>
> jshell> FileReader afr = new FileReader("/home/hank/source/txt/ribs.txt/")
> afr ==> java.io.FileReader@1698c449
>
> jshell> BufferedReader bfr = new BufferedReader(afr)
> bfr ==> java.io.BufferedReader@5ef04b5
>
> jshell> StringBuilder ct = new StringBuilder()
> ct ==>
>
> FileReader reads 2 bytes per character so, to get to the end, of the first
> hexdump line, let's walk 32 bytes:
>
> jshell> for (int i=0; i < 31; i++) {
>...> if ((value = bfr.read()) != -1) { ct.append((char) value); }
>...> i++;
>...> }
>
> jshell> ct
> ct ==> Try my delicious
>
> : 54 72 79 20 6d 79 20 64 65 6c 69 63 69 6f 75 73 Try my delicious
> T r y SP m y SP d e l i c i o u s (< YOU ARE
> HERE)
>
> : 54 72 79 20 6d 79 20 64 65 6c 69 63 69 6f 75 73 Try my delicious
> 0010: 20 70 6f 72 6b 2d 63 68 6f 70 20 72 69 62 73 21 pork-chop ribs!
> 0020: 0a .
>
> Now we iterate 31 more bytes, stopping short of the last character:
> jshell> for (int i=0; i < 30; i++) {
>...> if ((value = bfr.read()) != -1) { ct.append((char) value); }
>...> i++;
>...> }
>
> jshell> ct
> ct ==> Try my delicious pork-chop ribs
>
> : 54 72 79 20 6d 79 20 64 65 6c 69 63 69 6f 75 73 Try my delicious
> 0010: 20 70 6f 72 6b 2d 63 68 6f 70 20 72 69 62 73 21 pork-chop ribs!
> ^ we stopped here
>
> We just advance one more:
>
> jshell> if ((value = bfr.read()) != -1) { ct.append((char) value); }
>...>
>
> jshell> ct
> ct ==> Try my delicious pork-chop ribs!
>
> And one more time, to see if it borks:
> jshell> if ((value = bfr.read()) != -1) { ct.append((char) value); }
>
> jshell> ct
> ct ==> Try my delicious pork-chop ribs!
>
> Nope, everything looks fine. Now where does that '0xFFF" come from?!
> -- Hank
--
You received this message because you are subscribed to the Google
Groups "Clojure" group.
To post to this group, send email to clojure@googlegroups.com
Note that posts from new members are moderated - please be patient with your
first post.
To unsubscribe from this group, send email to
clojure+unsubscr...@googlegroups.com
For more
Re: Pesky java interop bug with 0xFFFFFFF error in BuferredReader
Hi Hank,
That loop/recur is still wrong because `loop` set bindings to define names
and gives initial values but `recur` does *not set bindings*, it just
provides new values.
So `recur` does not need a vector of bindings like `loop`
The pattern is as follow:
(loop [a-local-var "initial-value"]
(if (should-stop-looping? a-local-var)
(execute-last-expression a-local-var)
(recur a-new-local-var)))
In your pt8 function, you are reading your stream to many times in a loop,
if I write your pt8 function in procedural pseudo-code, this is what I get:
bfr = input-stream()
ct = string-buffer()
set loop-start // set loop point
with val, // set loop args
val = read(bfr) // set args initial value, first read
if !(val == -1) {
ct.append(char(read(bfr))) // read again! and lose previous byte!!
goto loop-start
with val = vector(val, read(bfr)) // read again! this byte will
be lost soon :(
}
ct.toString()
Regards,
Laurent
Le dimanche 26 décembre 2021 à 18:12:56 UTC+1, hank@gmail.com a écrit :
> Hi --
> Thanks for taking the time to help me.
> As far as I understand the examples, loop has this template:
>
> loop [binding]
> (condition
> (statement)
> (recur (binding)))
> And in 'recur' the loop is re-executed with new bindings.
>
> There was indeed an issue with the 'recur' outside 'when'. Thanks for
> pointing that out.
> I corrected that in the version below.
>
> I also changed to a smaller file (UTF-8 encoded in Linux), called
> 'ribs.txt', with the following content:
>
> source/txt on master [!?]
> ❯ cat ribs.txt
> Try my delicious pork-chop ribs!
>
> source/txt on master [!?]
> ❯ cat ribs.hexdump
> : 54 72 79 20 6d 79 20 64 65 6c 69 63 69 6f 75 73 Try my delicious
> 0010: 20 70 6f 72 6b 2d 63 68 6f 70 20 72 69 62 73 21 pork-chop ribs!
> 0020: 0a .
>
>
> (defn pt8 [file]
>(let [afr (FileReader. file); instances of FileReader, BufferedReader,
> StringBuffer
> bfr (BufferedReader. afr)
> ct (StringBuilder.)
> this-list (list afr bfr ct)]
> ; (apply println this-list)
> ; put recur INSIDE THE WHEN
> (loop [val (.read bfr)]
>(when (not (= val -1))
> (.append ct (Character/toChars (.read bfr)))
>(recur [val (.read bfr)])))
> ; when finished...
> (.toString ct)))
>
> I think this fixed the 'recur', because it does rebinding to a new call to
> "read()".
> However, the errors remains.
>
> user> (pt8 ribs)
> Execution error (IllegalArgumentException) at java.lang.Character/toChars
> (Character.java:8572).
> Not a valid Unicode code point: 0x
>
> The file used is sufficiently small so that we can walk the bytes using
> jshell:
>
> jshell> FileReader afr = new FileReader("/home/hank/source/txt/ribs.txt/")
> afr ==> java.io.FileReader@1698c449
>
> jshell> BufferedReader bfr = new BufferedReader(afr)
> bfr ==> java.io.BufferedReader@5ef04b5
>
> jshell> StringBuilder ct = new StringBuilder()
> ct ==>
>
> FileReader reads 2 bytes per character so, to get to the end, of the first
> hexdump line, let's walk 32 bytes:
>
> jshell> for (int i=0; i < 31; i++) {
>...> if ((value = bfr.read()) != -1) { ct.append((char) value); }
>...> i++;
>...> }
>
> jshell> ct
> ct ==> Try my delicious
>
> : 54 72 79 20 6d 79 20 64 65 6c 69 63 69 6f 75 73 Try my delicious
> T r y SP m y SP d e l i c i o u s (< YOU ARE
> HERE)
>
> : 54 72 79 20 6d 79 20 64 65 6c 69 63 69 6f 75 73 Try my delicious
> 0010: 20 70 6f 72 6b 2d 63 68 6f 70 20 72 69 62 73 21 pork-chop ribs!
> 0020: 0a .
>
> Now we iterate 31 more bytes, stopping short of the last character:
> jshell> for (int i=0; i < 30; i++) {
>...> if ((value = bfr.read()) != -1) { ct.append((char) value); }
>...> i++;
>...> }
>
> jshell> ct
> ct ==> Try my delicious pork-chop ribs
>
> : 54 72 79 20 6d 79 20 64 65 6c 69 63 69 6f 75 73 Try my delicious
> 0010: 20 70 6f 72 6b 2d 63 68 6f 70 20 72 69 62 73 21 pork-chop ribs!
> ^ we stopped here
>
> We just advance one more:
>
> jshell> if ((value = bfr.read()) != -1) { ct.append((char) value); }
>...>
>
> jshell> ct
> ct ==> Try my delicious pork-chop ribs!
>
> And one more time, to see if it borks:
> jshell> if ((value = bfr.read()) != -1) { ct.append((char) value); }
>
> jshell> ct
> ct ==> Try my delicious pork-chop ribs!
>
> Nope, everything looks fine. Now where does that '0xFFF" come from?!
> -- Hank
--
You received this message because you are subscribed to the Google
Groups "Clojure" group.
To post to this group, send email to clojure@googlegroups.com
Note that posts from new members are moderated - please be patient wi
Re: Pesky java interop bug with 0xFFFFFFF error in BuferredReader
Hi --
Thanks for taking the time to help me.
As far as I understand the examples, loop has this template:
loop [binding]
(condition
(statement)
(recur (binding)))
And in 'recur' the loop is re-executed with new bindings.
There was indeed an issue with the 'recur' outside 'when'. Thanks for
pointing that out.
I corrected that in the version below.
I also changed to a smaller file (UTF-8 encoded in Linux), called
'ribs.txt', with the following content:
source/txt on master [!?]
❯ cat ribs.txt
Try my delicious pork-chop ribs!
source/txt on master [!?]
❯ cat ribs.hexdump
: 54 72 79 20 6d 79 20 64 65 6c 69 63 69 6f 75 73 Try my delicious
0010: 20 70 6f 72 6b 2d 63 68 6f 70 20 72 69 62 73 21 pork-chop ribs!
0020: 0a .
(defn pt8 [file]
(let [afr (FileReader. file); instances of FileReader, BufferedReader,
StringBuffer
bfr (BufferedReader. afr)
ct (StringBuilder.)
this-list (list afr bfr ct)]
; (apply println this-list)
; put recur INSIDE THE WHEN
(loop [val (.read bfr)]
(when (not (= val -1))
(.append ct (Character/toChars (.read bfr)))
(recur [val (.read bfr)])))
; when finished...
(.toString ct)))
I think this fixed the 'recur', because it does rebinding to a new call to
"read()".
However, the errors remains.
user> (pt8 ribs)
Execution error (IllegalArgumentException) at java.lang.Character/toChars
(Character.java:8572).
Not a valid Unicode code point: 0x
The file used is sufficiently small so that we can walk the bytes using
jshell:
jshell> FileReader afr = new FileReader("/home/hank/source/txt/ribs.txt/")
afr ==> java.io.FileReader@1698c449
jshell> BufferedReader bfr = new BufferedReader(afr)
bfr ==> java.io.BufferedReader@5ef04b5
jshell> StringBuilder ct = new StringBuilder()
ct ==>
FileReader reads 2 bytes per character so, to get to the end, of the first
hexdump line, let's walk 32 bytes:
jshell> for (int i=0; i < 31; i++) {
...> if ((value = bfr.read()) != -1) { ct.append((char) value); }
...> i++;
...> }
jshell> ct
ct ==> Try my delicious
: 54 72 79 20 6d 79 20 64 65 6c 69 63 69 6f 75 73 Try my delicious
T r y SP m y SP d e l i c i o u s (< YOU ARE
HERE)
: 54 72 79 20 6d 79 20 64 65 6c 69 63 69 6f 75 73 Try my delicious
0010: 20 70 6f 72 6b 2d 63 68 6f 70 20 72 69 62 73 21 pork-chop ribs!
0020: 0a .
Now we iterate 31 more bytes, stopping short of the last character:
jshell> for (int i=0; i < 30; i++) {
...> if ((value = bfr.read()) != -1) { ct.append((char) value); }
...> i++;
...> }
jshell> ct
ct ==> Try my delicious pork-chop ribs
: 54 72 79 20 6d 79 20 64 65 6c 69 63 69 6f 75 73 Try my delicious
0010: 20 70 6f 72 6b 2d 63 68 6f 70 20 72 69 62 73 21 pork-chop ribs!
^ we stopped here
We just advance one more:
jshell> if ((value = bfr.read()) != -1) { ct.append((char) value); }
...>
jshell> ct
ct ==> Try my delicious pork-chop ribs!
And one more time, to see if it borks:
jshell> if ((value = bfr.read()) != -1) { ct.append((char) value); }
jshell> ct
ct ==> Try my delicious pork-chop ribs!
Nope, everything looks fine. Now where does that '0xFFF" come from?!
-- Hank
--
You received this message because you are subscribed to the Google
Groups "Clojure" group.
To post to this group, send email to clojure@googlegroups.com
Note that posts from new members are moderated - please be patient with your
first post.
To unsubscribe from this group, send email to
clojure+unsubscr...@googlegroups.com
For more options, visit this group at
http://groups.google.com/group/clojure?hl=en
---
You received this message because you are subscribed to the Google Groups
"Clojure" group.
To unsubscribe from this group and stop receiving emails from it, send an email
to clojure+unsubscr...@googlegroups.com.
To view this discussion on the web visit
https://groups.google.com/d/msgid/clojure/d3510982-bcaa-43c2-9461-aaae7be11f49n%40googlegroups.com.
Re: Pesky java interop bug with 0xFFFFFFF error in BuferredReader
Hank Your loop/recur in your pt5 function is still not good. Take the time to read the loop/recur documentation and to understand examples. A Clojure loop/recur is not really a loop like in other procedural languages. It is more akin to a new function call at the `loop` point with new args provided by the `recur` call. If you continue with the function call metaphor The `loop` call defines 3 things: - the starting point of the function - the argument name of the function - the **initial values** of those arguments When you need to call again that function with new arguments, you use `recur` with **new values**. When you don't need to recur, well... dont call `recur` :) and just evaluate a last expression which is the result of the `loop` expression. regards Laurent Le dimanche 26 décembre 2021 à 02:35:47 UTC+1, hank@gmail.com a écrit : > Thank for the answers. > Trying to recur with '(recur (.read bfr))' resulted in a: > Syntax error (UnsupportedOperationException) compiling recur at > (*cider-repl ~:localhost:41097(clj)*:237:9). > Can only recur from tail position > So I changed the code (see below). > > And now it complains that a previous form that was working '(.append > etc..') doesn't and the same error remains. > > user> (pt5 myfile) > > Execution error (IllegalArgumentException) at java.lang.Character/toChars > (Character.java:8572). > Not a valid Unicode code point: 0x > > (defn pt5 [file] > >(let [afr (FileReader. file); instances of FileReader, BufferedReader, > StringBuffer > bfr (BufferedReader. afr) > ct (StringBuilder.) > this-list (list afr bfr ct)] > ; (apply println this-list) > (loop [val (.read bfr)] >(when (not (= val -1)) > (.append ct (Character/toChars (.read bfr >(recur val)) > ; when finished... > (.toString ct))) > > Harder then it seemed at first sight... > -- Hank > > > -- You received this message because you are subscribed to the Google Groups "Clojure" group. To post to this group, send email to clojure@googlegroups.com Note that posts from new members are moderated - please be patient with your first post. To unsubscribe from this group, send email to clojure+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/clojure?hl=en --- You received this message because you are subscribed to the Google Groups "Clojure" group. To unsubscribe from this group and stop receiving emails from it, send an email to clojure+unsubscr...@googlegroups.com. To view this discussion on the web visit https://groups.google.com/d/msgid/clojure/66318891-e779-4a3c-818c-a235f7b32550n%40googlegroups.com.
Re: Pesky java interop bug with 0xFFFFFFF error in BuferredReader
Hi, In the quoted example the `recur` call is *inside* the `when` which is a huge difference because there is in this case an halting condition to get out of the loop ;) regards Laurent Le dimanche 26 décembre 2021 à 14:41:15 UTC+1, hank@gmail.com a écrit : > 2021-12-25, 21:11:46 UTC-3, LaurentJ wrote: > "Hi, > > Your loop/recur usage is wrong, your error may be because your loop has no > halting condition." > > Hi Laurent -- > I actually took inspiration from one of the sources you posted: > (import '(javax.sound.sampled AudioSystem AudioFormat$Encoding)) > > (let [mp3-file (java.io.File. "tryout.mp3") > audio-in (AudioSystem/getAudioInputStream mp3-file) > audio-decoded-in (AudioSystem/getAudioInputStream > AudioFormat$Encoding/PCM_SIGNED audio-in) > buffer (make-array Byte/TYPE 1024)] > (loop [] > (let [size (.read audio-decoded-in buffer)] > (when (> size 0) > ;do something with PCM data > (recur) > > > -- You received this message because you are subscribed to the Google Groups "Clojure" group. To post to this group, send email to clojure@googlegroups.com Note that posts from new members are moderated - please be patient with your first post. To unsubscribe from this group, send email to clojure+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/clojure?hl=en --- You received this message because you are subscribed to the Google Groups "Clojure" group. To unsubscribe from this group and stop receiving emails from it, send an email to clojure+unsubscr...@googlegroups.com. To view this discussion on the web visit https://groups.google.com/d/msgid/clojure/93ed9e36-bd43-4592-b5c3-89187304d75cn%40googlegroups.com.
Re: Pesky java interop bug with 0xFFFFFFF error in BuferredReader
2021-12-25, 21:11:46 UTC-3, LaurentJ wrote: "Hi, Your loop/recur usage is wrong, your error may be because your loop has no halting condition." Hi Laurent -- I actually took inspiration from one of the sources you posted: (import '(javax.sound.sampled AudioSystem AudioFormat$Encoding)) (let [mp3-file (java.io.File. "tryout.mp3") audio-in (AudioSystem/getAudioInputStream mp3-file) audio-decoded-in (AudioSystem/getAudioInputStream AudioFormat$Encoding/PCM_SIGNED audio-in) buffer (make-array Byte/TYPE 1024)] (loop [] (let [size (.read audio-decoded-in buffer)] (when (> size 0) ;do something with PCM data (recur) -- You received this message because you are subscribed to the Google Groups "Clojure" group. To post to this group, send email to clojure@googlegroups.com Note that posts from new members are moderated - please be patient with your first post. To unsubscribe from this group, send email to clojure+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/clojure?hl=en --- You received this message because you are subscribed to the Google Groups "Clojure" group. To unsubscribe from this group and stop receiving emails from it, send an email to clojure+unsubscr...@googlegroups.com. To view this discussion on the web visit https://groups.google.com/d/msgid/clojure/c293ceb0-d187-41f9-b0a4-68860cb55bd2n%40googlegroups.com.
Re: Pesky java interop bug with 0xFFFFFFF error in BuferredReader
Thanks, Harold. You see, that was an exercise in Java interop - I know about slurp, but I was trying to understand what was going on there. -- Hank -- You received this message because you are subscribed to the Google Groups "Clojure" group. To post to this group, send email to clojure@googlegroups.com Note that posts from new members are moderated - please be patient with your first post. To unsubscribe from this group, send email to clojure+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/clojure?hl=en --- You received this message because you are subscribed to the Google Groups "Clojure" group. To unsubscribe from this group and stop receiving emails from it, send an email to clojure+unsubscr...@googlegroups.com. To view this discussion on the web visit https://groups.google.com/d/msgid/clojure/dc222f28-0f21-4f02-b79c-1d0f4db4f95bn%40googlegroups.com.
Re: Pesky java interop bug with 0xFFFFFFF error in BuferredReader
Hank, Welcome. Great efforts- it certainly seems like you're learning a lot, and quickly. `clojure.core/slurp` is related, in case you haven't seen it yet: https://clojuredocs.org/clojure.core/slurp The implementation may also be enlightening: https://github.com/clojure/clojure/blob/clojure-1.10.3/src/clj/clojure/core.clj#L6944-L6954 It's natural when coming from non-functional languages to write `loop`-y code like you did, and while it's neat that Clojure enables writing code in that style (essential, actually, to the stated goal of pragmatism), it's not always helpful. In this case, the implementation of `slurp` also interops with Java to produce strings, but does so at a more helpful level of abstraction. I'll also note here that the https://ask.clojure.org/ site may be more fun for these types of discussions than the mailing list- though getting help anywhere (there are quite a few places actually) is of course fine. Best of luck, and warm wishes, -Harold On Saturday, December 25, 2021 at 6:35:47 PM UTC-7 hank@gmail.com wrote: > Thank for the answers. > Trying to recur with '(recur (.read bfr))' resulted in a: > Syntax error (UnsupportedOperationException) compiling recur at > (*cider-repl ~:localhost:41097(clj)*:237:9). > Can only recur from tail position > So I changed the code (see below). > > And now it complains that a previous form that was working '(.append > etc..') doesn't and the same error remains. > > user> (pt5 myfile) > > Execution error (IllegalArgumentException) at java.lang.Character/toChars > (Character.java:8572). > Not a valid Unicode code point: 0x > > (defn pt5 [file] > >(let [afr (FileReader. file); instances of FileReader, BufferedReader, > StringBuffer > bfr (BufferedReader. afr) > ct (StringBuilder.) > this-list (list afr bfr ct)] > ; (apply println this-list) > (loop [val (.read bfr)] >(when (not (= val -1)) > (.append ct (Character/toChars (.read bfr >(recur val)) > ; when finished... > (.toString ct))) > > Harder then it seemed at first sight... > -- Hank > > > -- You received this message because you are subscribed to the Google Groups "Clojure" group. To post to this group, send email to clojure@googlegroups.com Note that posts from new members are moderated - please be patient with your first post. To unsubscribe from this group, send email to clojure+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/clojure?hl=en --- You received this message because you are subscribed to the Google Groups "Clojure" group. To unsubscribe from this group and stop receiving emails from it, send an email to clojure+unsubscr...@googlegroups.com. To view this discussion on the web visit https://groups.google.com/d/msgid/clojure/87069aee-1320-4774-b214-bae29e0062f3n%40googlegroups.com.
Re: Pesky java interop bug with 0xFFFFFFF error in BuferredReader
Thank for the answers. Trying to recur with '(recur (.read bfr))' resulted in a: Syntax error (UnsupportedOperationException) compiling recur at (*cider-repl ~:localhost:41097(clj)*:237:9). Can only recur from tail position So I changed the code (see below). And now it complains that a previous form that was working '(.append etc..') doesn't and the same error remains. user> (pt5 myfile) Execution error (IllegalArgumentException) at java.lang.Character/toChars (Character.java:8572). Not a valid Unicode code point: 0x (defn pt5 [file] (let [afr (FileReader. file); instances of FileReader, BufferedReader, StringBuffer bfr (BufferedReader. afr) ct (StringBuilder.) this-list (list afr bfr ct)] ; (apply println this-list) (loop [val (.read bfr)] (when (not (= val -1)) (.append ct (Character/toChars (.read bfr (recur val)) ; when finished... (.toString ct))) Harder then it seemed at first sight... -- Hank -- You received this message because you are subscribed to the Google Groups "Clojure" group. To post to this group, send email to clojure@googlegroups.com Note that posts from new members are moderated - please be patient with your first post. To unsubscribe from this group, send email to clojure+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/clojure?hl=en --- You received this message because you are subscribed to the Google Groups "Clojure" group. To unsubscribe from this group and stop receiving emails from it, send an email to clojure+unsubscr...@googlegroups.com. To view this discussion on the web visit https://groups.google.com/d/msgid/clojure/17bab821-c47d-4791-b3ad-c56df51757a1n%40googlegroups.com.
Re: Pesky java interop bug with 0xFFFFFFF error in BuferredReader
I think at least part of the problem is your use of val in the let
statement. Inside the loop, you're testing (not (= val -1)), but val is an
immutable value defined above the loop as being the first character read
from the buffer, so it will always loop until it reads in the 0xFFF
that makes it crash. You probably want to modify your loop like this:
(loop [val (.read bfr)]
(when (not (= val -1))
(.append ct (Character/toChars val)))
(recur (.read bfr))
Now this re-assigns the next character from the buffer to val each time you
go through the loop.
I'm not a guru when it comes to Java interop, but I think the above is the
main problem you're having right now, so hopefully that will get you back
on track.
On Sat, Dec 25, 2021 at 2:23 PM Hank Lenzi wrote:
>
> Hello --
>
> I'm learning Clojure and its Java interop stuff. I am trying to emulate
> this function:
>
> public String readAllCharsOneByOne(BufferedReader bufferedReader) throws
> IOException {
> StringBuilder content = new StringBuilder();
>
> int value;
> while ((value = bufferedReader.read()) != -1) {
> content.append((char) value);
> }
>
> return content.toString();
> }
>
>
> So far, I've been able to reason that the parts I need are:
>
>
> (def myfile "/path/to/svenska_sample.txt")
> (import java.io.BufferedReader)
> (import java.io.FileReader)
> (import java.lang.StringBuilder)
> (import java.lang.Character)
>
> (def a-FileReader (FileReader. myfile))
> (def bufferedReader (BufferedReader. a-FileReader))
> (def content (StringBuilder.))
>
> which works
>
> user> (.append content (Character/toChars (.read bufferedReader)))
> #object[java.lang.StringBuilder 0x490447d0 "\nDe"]
> user> (.append content (Character/toChars (.read bufferedReader)))
> #object[java.lang.StringBuilder 0x490447d0 "\nDen"]
> user> (.append content (Character/toChars (.read bufferedReader)))
> #object[java.lang.StringBuilder 0x490447d0 "\nDen "]
> user> (.append content (Character/toChars (.read bufferedReader)))
> #object[java.lang.StringBuilder 0x490447d0 "\nDen t"]
> user> (.append content (Character/toChars (.read bufferedReader)))
> #object[java.lang.StringBuilder 0x490447d0 "\nDen ty"]
> user> (.append content (Character/toChars (.read bufferedReader)))
> #object[java.lang.StringBuilder 0x490447d0 "\nDen typ"]
> user> (.append content (Character/toChars (.read bufferedReader)))
> #object[java.lang.StringBuilder 0x490447d0 "\nDen typi"]
>
> The file is a small text file UTF-8 encoded in Linux with the following
> content:
>
> ❯ cat svenska_sample.txt
>
> Den typiska impulsiva olycksfågeln är en ung man som kraschar flera bilar,
> och ofta skryter lite med det, i varje fall när han är tillsammans med sina
> vänner._. För dem har otur i det närmaste blivit en livsstil, och de råkar
> konstant ut för olyckor, stora som små. Olycksfåglar kallar vi dem. Hur
> många det finns kan ingen med säkerhet säga, för det finns inga konkreta
> definitioner på denna grupp, och heller ingen given avgränsning av den. Att
> de finns, råder det emellertid ingen tvekan om, varken på sjukhusens
> akutmottagningar eller i försäkringsbranschen
>
> I wrote a function, with my brand new Clojure Java interop chops, that
> looks like this:
>
> ;; COMPILES - BUT CAN'T GET AROUND THE 0XFFF BUG
> (defn pt%% [file]
>(let [afr (FileReader. file); instances of FileReader, BufferedReader,
> StringBuffer
> bfr (BufferedReader. afr)
> ct (StringBuilder.)
> val (.read bfr)
> this-list (list afr bfr ct)]
> ; (apply println this-list)
> (loop []
>(when (not (= val -1))
> (.append ct (Character/toChars (.read bfr
>(recur))
> ; when finished...
> (.toString ct)))
>
> but it borks with the following error:
>
> user> (pt%% myfile)
> Execution error (IllegalArgumentException) at java.lang.Character/toChars
> (Character.java:8572).
> Not a valid Unicode code point: 0x
>
> What in the world could be causing this (NOTE: I am not a Java
> programmer)?
> Here is the hex dump of the file text file:
>
> ❯ cat svenska_sample.hexdump
> : 0a44 656e 2074 7970 6973 6b61 2069 6d70 .Den typiska imp
> 0010: 756c 7369 7661 206f 6c79 636b 7366 c3a5 ulsiva olycksf..
> 0020: 6765 6c6e 20c3 a472 2065 6e20 756e 6720 geln ..r en ung
> 0030: 6d61 6e20 736f 6d20 6b72 6173 6368 6172 man som kraschar
> 0040: 2066 6c65 7261 2062 696c 6172 2c20 6f63 flera bilar, oc
> 0050: 6820 6f66 7461 2073 6b72 7974 6572 206c h ofta skryter l
> 0060: 6974 6520 6d65 6420 6465 742c 2069 2076 ite med det, i v
> 0070: 6172 6a65 2066 616c 6c20 6ec3 a472 2068 arje fall n..r h
> 0080: 616e 20c3 a472 2074 696c 6c73 616d 6d61 an ..r tillsamma
> 0090: 6e73 206d 6564 2073 696e 6120 76c3 a46e ns med sina v..n
> 00a0: 6e65 722e 5f2e 2046 c3b6 7220 6465 6d20 ner._. F..r dem
> 00b0: 6861 7220 6f74 7572 2069 2064
Re: Pesky java interop bug with 0xFFFFFFF error in BuferredReader
Hi,
Your loop/recur usage is wrong, your error may be because your loop has no
halting condition.
https://clojure.org/reference/special_forms#loop
https://clojuredocs.org/clojure.core/loop
Regards
Laurent
Le samedi 25 décembre 2021 à 20:23:37 UTC+1, hank@gmail.com a écrit :
>
> Hello --
>
> I'm learning Clojure and its Java interop stuff. I am trying to emulate
> this function:
>
> public String readAllCharsOneByOne(BufferedReader bufferedReader) throws
> IOException {
> StringBuilder content = new StringBuilder();
>
> int value;
> while ((value = bufferedReader.read()) != -1) {
> content.append((char) value);
> }
>
> return content.toString();
> }
>
>
> So far, I've been able to reason that the parts I need are:
>
>
> (def myfile "/path/to/svenska_sample.txt")
> (import java.io.BufferedReader)
> (import java.io.FileReader)
> (import java.lang.StringBuilder)
> (import java.lang.Character)
>
> (def a-FileReader (FileReader. myfile))
> (def bufferedReader (BufferedReader. a-FileReader))
> (def content (StringBuilder.))
>
> which works
>
> user> (.append content (Character/toChars (.read bufferedReader)))
> #object[java.lang.StringBuilder 0x490447d0 "\nDe"]
> user> (.append content (Character/toChars (.read bufferedReader)))
> #object[java.lang.StringBuilder 0x490447d0 "\nDen"]
> user> (.append content (Character/toChars (.read bufferedReader)))
> #object[java.lang.StringBuilder 0x490447d0 "\nDen "]
> user> (.append content (Character/toChars (.read bufferedReader)))
> #object[java.lang.StringBuilder 0x490447d0 "\nDen t"]
> user> (.append content (Character/toChars (.read bufferedReader)))
> #object[java.lang.StringBuilder 0x490447d0 "\nDen ty"]
> user> (.append content (Character/toChars (.read bufferedReader)))
> #object[java.lang.StringBuilder 0x490447d0 "\nDen typ"]
> user> (.append content (Character/toChars (.read bufferedReader)))
> #object[java.lang.StringBuilder 0x490447d0 "\nDen typi"]
>
> The file is a small text file UTF-8 encoded in Linux with the following
> content:
>
> ❯ cat svenska_sample.txt
>
> Den typiska impulsiva olycksfågeln är en ung man som kraschar flera bilar,
> och ofta skryter lite med det, i varje fall när han är tillsammans med sina
> vänner._. För dem har otur i det närmaste blivit en livsstil, och de råkar
> konstant ut för olyckor, stora som små. Olycksfåglar kallar vi dem. Hur
> många det finns kan ingen med säkerhet säga, för det finns inga konkreta
> definitioner på denna grupp, och heller ingen given avgränsning av den. Att
> de finns, råder det emellertid ingen tvekan om, varken på sjukhusens
> akutmottagningar eller i försäkringsbranschen
>
> I wrote a function, with my brand new Clojure Java interop chops, that
> looks like this:
>
> ;; COMPILES - BUT CAN'T GET AROUND THE 0XFFF BUG
> (defn pt%% [file]
>(let [afr (FileReader. file); instances of FileReader, BufferedReader,
> StringBuffer
> bfr (BufferedReader. afr)
> ct (StringBuilder.)
> val (.read bfr)
> this-list (list afr bfr ct)]
> ; (apply println this-list)
> (loop []
>(when (not (= val -1))
> (.append ct (Character/toChars (.read bfr
>(recur))
> ; when finished...
> (.toString ct)))
>
> but it borks with the following error:
>
> user> (pt%% myfile)
> Execution error (IllegalArgumentException) at java.lang.Character/toChars
> (Character.java:8572).
> Not a valid Unicode code point: 0x
>
> What in the world could be causing this (NOTE: I am not a Java
> programmer)?
> Here is the hex dump of the file text file:
>
> ❯ cat svenska_sample.hexdump
> : 0a44 656e 2074 7970 6973 6b61 2069 6d70 .Den typiska imp
> 0010: 756c 7369 7661 206f 6c79 636b 7366 c3a5 ulsiva olycksf..
> 0020: 6765 6c6e 20c3 a472 2065 6e20 756e 6720 geln ..r en ung
> 0030: 6d61 6e20 736f 6d20 6b72 6173 6368 6172 man som kraschar
> 0040: 2066 6c65 7261 2062 696c 6172 2c20 6f63 flera bilar, oc
> 0050: 6820 6f66 7461 2073 6b72 7974 6572 206c h ofta skryter l
> 0060: 6974 6520 6d65 6420 6465 742c 2069 2076 ite med det, i v
> 0070: 6172 6a65 2066 616c 6c20 6ec3 a472 2068 arje fall n..r h
> 0080: 616e 20c3 a472 2074 696c 6c73 616d 6d61 an ..r tillsamma
> 0090: 6e73 206d 6564 2073 696e 6120 76c3 a46e ns med sina v..n
> 00a0: 6e65 722e 5f2e 2046 c3b6 7220 6465 6d20 ner._. F..r dem
> 00b0: 6861 7220 6f74 7572 2069 2064 6574 206e har otur i det n
> 00c0: c3a4 726d 6173 7465 2062 6c69 7669 7420 ..rmaste blivit
> 00d0: 656e 206c 6976 7373 7469 6c2c 206f 6368 en livsstil, och
> 00e0: 2064 6520 72c3 a56b 6172 206b 6f6e 7374 de r..kar konst
> 00f0: 616e 7420 7574 2066 c3b6 7220 6f6c 7963 ant ut f..r olyc
> 0100: 6b6f 722c 2073 746f 7261 2073 6f6d 2073 kor, stora som s
> 0110: 6dc3 a52e 204f 6c79 636b 7366 c3a5 676c m... Olycksf..gl
> 0
