Probably stupid... question about string printString.
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Probably stupid... question about string printString.
 
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Hi
I would like to really understand why 'foo' printString >>> '''foo''' and not why this is not 'foo' itself. Stef |
Re: Probably stupid... question about string printString.
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On Sat, Oct 21, 2017 at 05:28:21PM +0200, Stephane Ducasse wrote:
> Hi > > I would like to really understand why > 'foo' printString > >>> > '''foo''' > > and not why this is not > > 'foo' > > itself. > > Stef I can't comment on the original thinking behind this, but I agree that something like: String>>printOn: aStream "Represent the receiver on the supplied stream" aStream nextPutAll: self would be much better. If we're displaying values such as numbers and strings in a UI, e.g. table, we normally don't want the strings always enclosed in quotes. Cheers, Alistair |
Re: Probably stupid... question about string printString.
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Yes this is my point. I was surprised to get ' on the transcript.
Stef On Sat, Oct 21, 2017 at 7:49 PM, Alistair Grant <[hidden email]> wrote: > On Sat, Oct 21, 2017 at 05:28:21PM +0200, Stephane Ducasse wrote: >> Hi >> >> I would like to really understand why >> 'foo' printString >> >>> >> '''foo''' >> >> and not why this is not >> >> 'foo' >> >> itself. >> >> Stef > > I can't comment on the original thinking behind this, but I agree that > something like: > > > String>>printOn: aStream > "Represent the receiver on the supplied stream" > > aStream nextPutAll: self > > > > would be much better. > > If we're displaying values such as numbers and strings in a UI, e.g. > table, we normally don't want the strings always enclosed in quotes. > > Cheers, > Alistair > > |
Re: Probably stupid... question about string printString.
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No. nextPutAll: self is not a good solution at all. Try it, and you'll get foo, not 'foo'.2017-10-21 21:12 GMT+02:00 Stephane Ducasse <[hidden email]>: Yes this is my point. I was surprised to get ' on the transcript. |
Re: Probably stupid... question about string printString.
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IOW, if you want to print 'foo', just print 'foo', but don't print 'foo' printString. 2017-10-21 22:10 GMT+02:00 Nicolas Cellier <[hidden email]>:
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Re: Probably stupid... question about string printString.
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Hi Nicolas,
On Sat, Oct 21, 2017 at 10:12:06PM +0200, Nicolas Cellier wrote: > IOW, if you want to print 'foo', just print 'foo', but don't print 'foo' > printString. > > 2017-10-21 22:10 GMT+02:00 Nicolas Cellier <[hidden email]> > : > > No. nextPutAll: self is not a good solution at all. > Try it, and you'll get foo, not 'foo'. > > 'foo' printString has exactly 5 letters: $' $f $o $o $' so it does what you > want. But what I want is the 3 letters in foo. Think about displaying a table of values. If it contains a mixture of numbers and strings, what I want to see is: 1 | string one | 3.1415 | string two not: 1 | 'string one' | 3.1415 | 'string two' If I want the second form (with quotes) I can use #storeString / #storeOn:. What is the one message that I can send to a mixture of numbers and strings that will return a string (or write to a stream) that will display as shown in the first example above? Thanks, Alistair > The problem is when you want to print 'foo' printString. > You are in fact doing 'foo' printString printOn: aStream, IOW aStream > nextPutAll: 'foo' printString printString. > > > 2017-10-21 21:12 GMT+02:00 Stephane Ducasse <[hidden email]>: > > Yes this is my point. I was surprised to get ' on the transcript. > > Stef > > On Sat, Oct 21, 2017 at 7:49 PM, Alistair Grant <[hidden email]> > wrote: > > On Sat, Oct 21, 2017 at 05:28:21PM +0200, Stephane Ducasse wrote: > >> Hi > >> > >> I would like to really understand why > >> 'foo' printString > >> >>> > >> '''foo''' > >> > >> and not why this is not > >> > >> 'foo' > >> > >> itself. > >> > >> Stef > > > > I can't comment on the original thinking behind this, but I agree > that > > something like: > > > > > > String>>printOn: aStream > > "Represent the receiver on the supplied stream" > > > > aStream nextPutAll: self > > > > > > > > would be much better. > > > > If we're displaying values such as numbers and strings in a UI, e.g. > > table, we normally don't want the strings always enclosed in quotes. > > > > Cheers, > > Alistair > > > > > > > > > |
Re: Probably stupid... question about string printString.
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In reply to this post by alistairgrant
Alistair Grant wrote:
> I can't comment on the original thinking behind this The original thinking is simple and as the name says: you want to print the object (even when it is a string) to be print in a string. So it always is a "printObjectInString" instead of a "printObjectAsString" behavior. Also the resulting string often is a string to easily reconstruct the object. So it is not a conversion method. There is #asString for that. > If we're displaying values such as numbers and strings in a UI, e.g. > table, we normally don't want the strings always enclosed in quotes. There is #displayString for this task (which may return the printString or is overwritten) and this is common in nearly all Smalltalks I know. Bye T. |
Re: Probably stupid... question about string printString.
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In reply to this post by Nicolas Cellier
Nicolas
the problem is that I do not know if I will get a string or an object. the arg gets printStringed (instead of asString). Now if I want to have the correct behavior I will have to type check. Still I do not understand why printString a string wrap it 'foo' printString evaluating to 'foo' vs. 'foo' printString evaluating to '''foo''' There is something unclear to me around string representation and object representation as string. @Alistair In fact we should use displayString to call a printString for UI (list...) On Sat, Oct 21, 2017 at 10:10 PM, Nicolas Cellier <[hidden email]> wrote: > No. nextPutAll: self is not a good solution at all. > Try it, and you'll get foo, not 'foo'. > > 'foo' printString has exactly 5 letters: $' $f $o $o $' so it does what you > want. > > The problem is when you want to print 'foo' printString. > You are in fact doing 'foo' printString printOn: aStream, IOW aStream > nextPutAll: 'foo' printString printString. > > > 2017-10-21 21:12 GMT+02:00 Stephane Ducasse <[hidden email]>: >> >> Yes this is my point. I was surprised to get ' on the transcript. >> >> Stef >> >> On Sat, Oct 21, 2017 at 7:49 PM, Alistair Grant <[hidden email]> >> wrote: >> > On Sat, Oct 21, 2017 at 05:28:21PM +0200, Stephane Ducasse wrote: >> >> Hi >> >> >> >> I would like to really understand why >> >> 'foo' printString >> >> >>> >> >> '''foo''' >> >> >> >> and not why this is not >> >> >> >> 'foo' >> >> >> >> itself. >> >> >> >> Stef >> > >> > I can't comment on the original thinking behind this, but I agree that >> > something like: >> > >> > >> > String>>printOn: aStream >> > "Represent the receiver on the supplied stream" >> > >> > aStream nextPutAll: self >> > >> > >> > >> > would be much better. >> > >> > If we're displaying values such as numbers and strings in a UI, e.g. >> > table, we normally don't want the strings always enclosed in quotes. >> > >> > Cheers, >> > Alistair >> > >> > >> > |
Re: Probably stupid... question about string printString.
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In reply to this post by alistairgrant
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> But what I want is the 3 letters in foo. > > Think about displaying a table of values. If it contains a mixture of > numbers and strings, what I want to see is: > > 1 | string one | 3.1415 | string two > > not: > > 1 | 'string one' | 3.1415 | 'string two' > > > If I want the second form (with quotes) I can use #storeString / #storeOn:. indeed. I do not get printString in String is storeOn: > What is the one message that I can send to a mixture of numbers and > strings that will return a string (or write to a stream) that will > display as shown in the first example above? Yes this is my point. In fact I do not know what I get. So now I'm forced to type check. Stef > > > Thanks, > Alistair > > > >> The problem is when you want to print 'foo' printString. >> You are in fact doing 'foo' printString printOn: aStream, IOW aStream >> nextPutAll: 'foo' printString printString. >> >> >> 2017-10-21 21:12 GMT+02:00 Stephane Ducasse <[hidden email]>: >> >> Yes this is my point. I was surprised to get ' on the transcript. >> >> Stef >> >> On Sat, Oct 21, 2017 at 7:49 PM, Alistair Grant <[hidden email]> >> wrote: >> > On Sat, Oct 21, 2017 at 05:28:21PM +0200, Stephane Ducasse wrote: >> >> Hi >> >> >> >> I would like to really understand why >> >> 'foo' printString >> >> >>> >> >> '''foo''' >> >> >> >> and not why this is not >> >> >> >> 'foo' >> >> >> >> itself. >> >> >> >> Stef >> > >> > I can't comment on the original thinking behind this, but I agree >> that >> > something like: >> > >> > >> > String>>printOn: aStream >> > "Represent the receiver on the supplied stream" >> > >> > aStream nextPutAll: self >> > >> > >> > >> > would be much better. >> > >> > If we're displaying values such as numbers and strings in a UI, e.g. >> > table, we normally don't want the strings always enclosed in quotes. >> > >> > Cheers, >> > Alistair >> > >> > >> >> >> >> >> > |
Re: Probably stupid... question about string printString.
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In reply to this post by Torsten Bergmann
Hi Torsten,
On Sun, Oct 22, 2017 at 10:40:41AM +0200, Torsten Bergmann wrote: > Alistair Grant wrote: > > I can't comment on the original thinking behind this > > The original thinking is simple and as the name says: you want to print the > object (even when it is a string) to be print in a string. > > So it always is a "printObjectInString" instead of a "printObjectAsString" > behavior. Also the resulting string often is a string to easily reconstruct the object. > > So it is not a conversion method. There is #asString for that. Hmm, I knew about #asString, but this was a while ago, so I can't remember why I didn't use it. But thanks for the reminder. > > If we're displaying values such as numbers and strings in a UI, e.g. > > table, we normally don't want the strings always enclosed in quotes. > > There is #displayString for this task (which may return the printString or is overwritten) > and this is common in nearly all Smalltalks I know. Right, so what would be nice is for UI elements / GT toolkit to move to using #displayString by default, and to add String>>displayString that answers the receiver (currently in Pharo String uses the default #printString, which returns the string with quotes). From memory this has been discussed before, but I couldn't find it, and don't remember the outcome. Thanks, Alistair |
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