Printing hexadecimal values of a string
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Printing hexadecimal values of a string
 
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Hello all,
I get a strange behaviour while trying to print hexadecimal values of a string. Context: I get a SHA1 hash from a binary stream, store it into a string, and I want to display that string (using asHex). Problem: for values inferior to 16, the leading zero is ignored. (15 -> 'F' instead of '0F'). I could modify SmallInteger>>printStringBase: to always include the leading zero, but I fear I'm going to break a lot of code doing that. Is there a better way to fix my problem? apart from using directly the following: aStream do:[:val | val printStringBase:16 nDigits:2] Best regards, Geoffroy |
Re: Printing hexadecimal values of a string
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Hi Geoffroy,
On 19 Dec 2010, at 21:55, Geoffroy Couprie wrote: > Hello all, > > I get a strange behaviour while trying to print hexadecimal values of a string. > > Context: I get a SHA1 hash from a binary stream, store it into a > string, and I want to display that string (using asHex). > > Problem: for values inferior to 16, the leading zero is ignored. (15 > -> 'F' instead of '0F'). > > I could modify SmallInteger>>printStringBase: to always include the > leading zero, but I fear I'm going to break a lot of code doing that. > Is there a better way to fix my problem? apart from using directly the > following: > aStream do:[:val | val printStringBase:16 nDigits:2] > > Best regards, > > Geoffroy Why would you not use the ByteArray>>#hex method ? #(0 1 2 253 254 255) asByteArray hex '000102fdfeff' Sven |
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I know how your feel. My code:
hexHashFrom: aByteString "#hex will omit a leading 0. If that's the case insert leading 0." ^aByteString asByteArray hex asLowercase forceTo: 40 paddingStartWith: $0 Max On 19.12.2010, at 22:54, Sven Van Caekenberghe wrote: > Hi Geoffroy, > > On 19 Dec 2010, at 21:55, Geoffroy Couprie wrote: > >> Hello all, >> >> I get a strange behaviour while trying to print hexadecimal values of a string. >> >> Context: I get a SHA1 hash from a binary stream, store it into a >> string, and I want to display that string (using asHex). >> >> Problem: for values inferior to 16, the leading zero is ignored. (15 >> -> 'F' instead of '0F'). >> >> I could modify SmallInteger>>printStringBase: to always include the >> leading zero, but I fear I'm going to break a lot of code doing that. >> Is there a better way to fix my problem? apart from using directly the >> following: >> aStream do:[:val | val printStringBase:16 nDigits:2] >> >> Best regards, >> >> Geoffroy > > Why would you not use the ByteArray>>#hex method ? > > #(0 1 2 253 254 255) asByteArray hex > > '000102fdfeff' > > Sven > > |
Re: Printing hexadecimal values of a string
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In reply to this post by Geoffroy Couprie
On Dec 19, 2010, at 9:55 PM, Geoffroy Couprie wrote: > Hello all, > > I get a strange behaviour while trying to print hexadecimal values of a string. > > Context: I get a SHA1 hash from a binary stream, store it into a > string, and I want to display that string (using asHex). > > Problem: for values inferior to 16, the leading zero is ignored. (15 > -> 'F' instead of '0F'). indeed printStringHex prints F instead of 0F 15 printStringHex 'F' 15 hex '16rF' Geoffroy could you add a variant that produces the correct behavior with some tests? > I could modify SmallInteger>>printStringBase: to always include the > leading zero, but I fear I'm going to break a lot of code doing that. > Is there a better way to fix my problem? apart from using directly the > following: > aStream do:[:val | val printStringBase:16 nDigits:2] > > Best regards, > > Geoffroy > |
Re: Printing hexadecimal values of a string
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In reply to this post by Max Leske
max on which class do you define it?
do you have some tests? Stef On Dec 19, 2010, at 11:40 PM, Max Leske wrote: > I know how your feel. My code: > > hexHashFrom: aByteString > "#hex will omit a leading 0. If that's the case insert leading 0." > ^aByteString asByteArray hex asLowercase forceTo: 40 paddingStartWith: $0 > > Max > > > On 19.12.2010, at 22:54, Sven Van Caekenberghe wrote: > >> Hi Geoffroy, >> >> On 19 Dec 2010, at 21:55, Geoffroy Couprie wrote: >> >>> Hello all, >>> >>> I get a strange behaviour while trying to print hexadecimal values of a string. >>> >>> Context: I get a SHA1 hash from a binary stream, store it into a >>> string, and I want to display that string (using asHex). >>> >>> Problem: for values inferior to 16, the leading zero is ignored. (15 >>> -> 'F' instead of '0F'). >>> >>> I could modify SmallInteger>>printStringBase: to always include the >>> leading zero, but I fear I'm going to break a lot of code doing that. >>> Is there a better way to fix my problem? apart from using directly the >>> following: >>> aStream do:[:val | val printStringBase:16 nDigits:2] >>> >>> Best regards, >>> >>> Geoffroy >> >> Why would you not use the ByteArray>>#hex method ? >> >> #(0 1 2 253 254 255) asByteArray hex >> >> '000102fdfeff' >> >> Sven >> >> > > |
Re: Printing hexadecimal values of a string
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In reply to this post by Stéphane Ducasse
On Mon, 20 Dec 2010, Stéphane Ducasse wrote:
> > > On Dec 19, 2010, at 9:55 PM, Geoffroy Couprie wrote: > >> Hello all, >> >> I get a strange behaviour while trying to print hexadecimal values of a string. >> >> Context: I get a SHA1 hash from a binary stream, store it into a >> string, and I want to display that string (using asHex). >> >> Problem: for values inferior to 16, the leading zero is ignored. (15 >> -> 'F' instead of '0F'). > > indeed printStringHex prints F instead of 0F > 15 printStringHex > 'F' > 15 hex > '16rF' > > Geoffroy could you add a variant that produces the correct behavior with some tests? #hex. Since his stream is already binary, he can also avoid converting his data to a string. Levente > >> I could modify SmallInteger>>printStringBase: to always include the >> leading zero, but I fear I'm going to break a lot of code doing that. >> Is there a better way to fix my problem? apart from using directly the >> following: >> aStream do:[:val | val printStringBase:16 nDigits:2] >> >> Best regards, >> >> Geoffroy >> > > > |
Re: Printing hexadecimal values of a string
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Hello,
2010/12/20 Levente Uzonyi <[hidden email]>: > On Mon, 20 Dec 2010, Stéphane Ducasse wrote: > >> >> >> On Dec 19, 2010, at 9:55 PM, Geoffroy Couprie wrote: >> >>> Hello all, >>> >>> I get a strange behaviour while trying to print hexadecimal values of a >>> string. >>> >>> Context: I get a SHA1 hash from a binary stream, store it into a >>> string, and I want to display that string (using asHex). >>> >>> Problem: for values inferior to 16, the leading zero is ignored. (15 >>> -> 'F' instead of '0F'). >> >> indeed printStringHex prints F instead of 0F >> 15 printStringHex >> 'F' >> 15 hex >> '16rF' >> >> Geoffroy could you add a variant that produces the correct behavior with >> some tests? > > No need to do that. As Sven pointed out, he can simply use ByteArray >> > #hex. Since his stream is already binary, he can also avoid converting his > data to a string. > More context: I am using a ZLibReadStream and its upTo: method, which gives me a ByteString, not a ByteArray. I guess I could convert it to a ByteArray. But I still think there's a bug here: printing the hex value of a Character should add the leading zero, because they're represented by a full byte. So, I propose this change: Character>>hex ^value printStringBase: 16 nDigits: 2 |
Re: Printing hexadecimal values of a string
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On Mon, 20 Dec 2010, Geoffroy Couprie wrote:
> Hello, > > 2010/12/20 Levente Uzonyi <[hidden email]>: >> On Mon, 20 Dec 2010, Stéphane Ducasse wrote: >> >>> >>> >>> On Dec 19, 2010, at 9:55 PM, Geoffroy Couprie wrote: >>> >>>> Hello all, >>>> >>>> I get a strange behaviour while trying to print hexadecimal values of a >>>> string. >>>> >>>> Context: I get a SHA1 hash from a binary stream, store it into a >>>> string, and I want to display that string (using asHex). >>>> >>>> Problem: for values inferior to 16, the leading zero is ignored. (15 >>>> -> 'F' instead of '0F'). >>> >>> indeed printStringHex prints F instead of 0F >>> 15 printStringHex >>> 'F' >>> 15 hex >>> '16rF' >>> >>> Geoffroy could you add a variant that produces the correct behavior with >>> some tests? >> >> No need to do that. As Sven pointed out, he can simply use ByteArray >> >> #hex. Since his stream is already binary, he can also avoid converting his >> data to a string. >> > > More context: I am using a ZLibReadStream and its upTo: method, which > gives me a ByteString, not a ByteArray. I guess I could convert it to > a ByteArray. > > But I still think there's a bug here: printing the hex value of a > Character should add the leading zero, because they're represented by > a full byte. > > So, I propose this change: > > Character>>hex > ^value printStringBase: 16 nDigits: 2 > > (Character value: 12345) hex Levente |
Re: Printing hexadecimal values of a string
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2010/12/20 Levente Uzonyi <[hidden email]>:
> On Mon, 20 Dec 2010, Geoffroy Couprie wrote: > >> Hello, >> >> 2010/12/20 Levente Uzonyi <[hidden email]>: >>> >>> On Mon, 20 Dec 2010, Stéphane Ducasse wrote: >>> >>>> >>>> >>>> On Dec 19, 2010, at 9:55 PM, Geoffroy Couprie wrote: >>>> >>>>> Hello all, >>>>> >>>>> I get a strange behaviour while trying to print hexadecimal values of a >>>>> string. >>>>> >>>>> Context: I get a SHA1 hash from a binary stream, store it into a >>>>> string, and I want to display that string (using asHex). >>>>> >>>>> Problem: for values inferior to 16, the leading zero is ignored. (15 >>>>> -> 'F' instead of '0F'). >>>> >>>> indeed printStringHex prints F instead of 0F >>>> 15 printStringHex >>>> 'F' >>>> 15 hex >>>> '16rF' >>>> >>>> Geoffroy could you add a variant that produces the correct behavior with >>>> some tests? >>> >>> No need to do that. As Sven pointed out, he can simply use ByteArray >> >>> #hex. Since his stream is already binary, he can also avoid converting >>> his >>> data to a string. >>> >> >> More context: I am using a ZLibReadStream and its upTo: method, which >> gives me a ByteString, not a ByteArray. I guess I could convert it to >> a ByteArray. >> >> But I still think there's a bug here: printing the hex value of a >> Character should add the leading zero, because they're represented by >> a full byte. >> >> So, I propose this change: >> >> Character>>hex >> ^value printStringBase: 16 nDigits: 2 >> >> > > What about this? > > (Character value: 12345) hex > Huh, I forgot multibyte characters... Then would this be sufficient? Character>>hex value >255 ifTrue: [^value hex] ifFalse: [^value printStringBase: 16 nDigits: 2] |
Re: Printing hexadecimal values of a string
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>
> Huh, I forgot multibyte characters... Then would this be sufficient? > > Character>>hex > value >255 > ifTrue: [^value hex] > ifFalse: [^value printStringBase: 16 nDigits: 2] > geoffroy we cannot really change hex because hex returns 16rXXX and the other classes are consistent with that. (Character value: 12345) hex '16r3039' Integer>>hex "Print the receiver as hex, prefixed with 16r. DO NOT CHANGE THIS! The Cog VMMaker depends on this. Consider using any of printStringHex printStringBase: 16 printStringBase: 16 length: 8 padded: true storeStringHex storeStringBase: 16 storeStringBase: 16 length: 11 padded: true" ^self storeStringBase: 16 Now what we could have is another method named: xxPrintStringHex for example (first name that came to my mind) paddedPrintStringHex 1566 printStringHex '61E' 15 printStringHex 'F' 1566 paddedPrintStringHex '61E' 15 paddedPrintStringHex '0F' Or something like that. Stef |
Re: Printing hexadecimal values of a string
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On Mon, Dec 20, 2010 at 1:31 PM, Stéphane Ducasse
<[hidden email]> wrote: >> >> Huh, I forgot multibyte characters... Then would this be sufficient? >> >> Character>>hex >> value >255 >> ifTrue: [^value hex] >> ifFalse: [^value printStringBase: 16 nDigits: 2] >> > > geoffroy > > we cannot really change hex because hex returns > 16rXXX > > and the other classes are consistent with that. > > (Character value: 12345) hex > '16r3039' > > > Integer>>hex > "Print the receiver as hex, prefixed with 16r. DO NOT CHANGE THIS! The Cog VMMaker depends on this. > Consider using any of > printStringHex > printStringBase: 16 > printStringBase: 16 length: 8 padded: true > storeStringHex > storeStringBase: 16 > storeStringBase: 16 length: 11 padded: true" > ^self storeStringBase: 16 > > Now what we could have is another method named: > xxPrintStringHex > for example (first name that came to my mind) > paddedPrintStringHex > > 1566 printStringHex '61E' > > 15 printStringHex > 'F' > > 1566 paddedPrintStringHex '61E' > > 15 paddedPrintStringHex > '0F' > > Or something like that. > I was using Pharo 1.1, where PrintStringHex is not implemented. In the patch for issue 3466, I modified printStringHex, but a new function including padding might be a better idea. Until Pharo 1.2 is published, I'll keep my custom code to display hexadecimal strings. |
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In reply to this post by Stéphane Ducasse
Hi Stef
Sorry, I should have been more specific. This is a method I use in my own application. I'm not sure if I did test the method but I could have a look if you like. Max On 20.12.2010, at 09:11, Stéphane Ducasse wrote: > max on which class do you define it? > > do you have some tests? > > Stef > > On Dec 19, 2010, at 11:40 PM, Max Leske wrote: > >> I know how your feel. My code: >> >> hexHashFrom: aByteString >> "#hex will omit a leading 0. If that's the case insert leading 0." >> ^aByteString asByteArray hex asLowercase forceTo: 40 paddingStartWith: $0 >> >> Max >> >> >> On 19.12.2010, at 22:54, Sven Van Caekenberghe wrote: >> >>> Hi Geoffroy, >>> >>> On 19 Dec 2010, at 21:55, Geoffroy Couprie wrote: >>> >>>> Hello all, >>>> >>>> I get a strange behaviour while trying to print hexadecimal values of a string. >>>> >>>> Context: I get a SHA1 hash from a binary stream, store it into a >>>> string, and I want to display that string (using asHex). >>>> >>>> Problem: for values inferior to 16, the leading zero is ignored. (15 >>>> -> 'F' instead of '0F'). >>>> >>>> I could modify SmallInteger>>printStringBase: to always include the >>>> leading zero, but I fear I'm going to break a lot of code doing that. >>>> Is there a better way to fix my problem? apart from using directly the >>>> following: >>>> aStream do:[:val | val printStringBase:16 nDigits:2] >>>> >>>> Best regards, >>>> >>>> Geoffroy >>> >>> Why would you not use the ByteArray>>#hex method ? >>> >>> #(0 1 2 253 254 255) asByteArray hex >>> >>> '000102fdfeff' >>> >>> Sven >>> >>> >> >> > > |
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In reply to this post by Stéphane Ducasse
I don't want to start a philosophical discussion, but I'm puzzled: What constitutes "correct" behaviour in this case?
Are you saying that 'correct' would be something like: 1 printStringHex '0F' and 1 hex '16r01' ?? Em 20/12/2010 06:10, Stéphane Ducasse < [hidden email] > escreveu: On Dec 19, 2010, at 9:55 PM, Geoffroy Couprie wrote: > Hello all, > > I get a strange behaviour while trying to print hexadecimal values of a string. > > Context: I get a SHA1 hash from a binary stream, store it into a > string, and I want to display that string (using asHex). > > Problem: for values inferior to 16, the leading zero is ignored. (15 > -> 'F' instead of '0F'). indeed printStringHex prints F instead of 0F 15 printStringHex 'F' 15 hex '16rF' Geoffroy could you add a variant that produces the correct behavior with some tests? > I could modify SmallInteger>>printStringBase: to always include the > leading zero, but I fear I'm going to break a lot of code doing that. > Is there a better way to fix my problem? apart from using directly the > following: > aStream do:[:val | val printStringBase:16 nDigits:2] > > Best regards, > > Geoffroy > |
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