On 14 October 2012 13:56, Levente Uzonyi <[email protected]> wrote: > On Sun, 14 Oct 2012, Igor Stasenko wrote: > >> A total number of lines in string should be: >> one + number of line separators found. >> >> Explanation: a 'String cr/ crlf' stands for 'line separator'. >> By definition, a separator, is thing which separates two others.. i >> mean, there is no way how you can use 'separator' term >> without having TWO things which it separates. >> >> The problem is that #lines does not follows common sense: >> >> (String empty, String cr, String empty) lines size 1 >> >> so, our line separator "separates" one thing :) >> It means that we overload the definition: >> - a line separator separates two lines unless it is at the end of text. >> >> But think , how dearly this 'unless' will costs in terms of >> implementation! >> Everywhere where you may need to handle text, you should put this >> extra rule, and if you forget it, >> you will be punished.. >> >> >> Here what various #lines produces: >> >> ( 'A' ) lines size 1 >> ( 'A', String cr ) lines size 1 !!oops!!. >> >> ( String cr, 'A' ) lines size 2 >> ( 'A', String cr, 'A' ) lines size 2 >> >> ( 'A', String cr, 'A', String cr ) lines size 2 >> ( 'A', String cr, 'A', String cr ) lines size 2 !!oops!! > > > The above two examples are the same. ;) > oh,sorry, i meant ( 'A', String cr, 'A' ) lines size 2 ( 'A', String cr, , 'A', String cr ) lines size 2 !!oops!!
> >> >> You may think this is fine, but lets look at the problem from another >> angle: >> >> self assert: (string1, String cr, string2) lineCount >= 2 >> >> The 'string1, String cr, string2' above is an insertion operation. >> We inserting a line separator between two arbitrary strings. >> Now, in what universe the total number of lines may not get increased >> after such insertion? >> >> So, it is simply inconsistent. Or maybe you happy to put extra code >> everywhere where you handling text, to do a special handling if last >> character is line separator? >> But we can avoid all that mess it in a first place, if we obey to common >> sense. > > > Read this before you do anything (wrong): > > "There is also some confusion whether newlines terminate or separate lines. > If a newline is considered a separator, there will be no newline after the > last line of a file. The general convention on most systems is to add a > newline even after the last line, i.e. to treat newline as a line > terminator.[citation needed] Some programs have problems processing the last > line of a file if it is not newline terminated. Conversely, programs that > expect newline to be used as a separator will interpret a final newline as > starting a new (empty) line." > I am more concerned about out little world in smalltalk. For instance, how we count number of lines in text editor. Let me demonstrate what way counting the number of lines is consistent with editor: when user opens a fresh editor with empty contents, he has a single empty line for editing: 1: '' now he can start typing: 1: 'abc' if you save this string into file, and load it back, you obviously should show same contents: 1: 'abc' so, even if there's no 'newline' at the end it is still 1 line of text. If you won't keep same perception between what you showing to user and how tools perceive it, you will get inconsistency (with all grave consequences, and numerous workarounds everywhere etc etc ) 'wc -l' shows you 0, while editor shows 1, so there is no consistency. If we favor user's experience, then in such perception, the real liar is wc, not text editor. now, lets assume that user continues editing that text and hits "enter". No matter what character(s) you will insert into the string contents (lf/cr/crlf whatever), you should now show TWO lines available for editing: 1: 'abc' 2: '' So, again, it is not a question, that most consistent way of treating cr/crlf/lf is to be a line separator, but not 'line terminating character(s)' or 'new line, but not always' bullshit. Now, you can say, that editor don't needs to be pedantic about it, and start not from empty string but from '' , String cr contents. But then users will lose ability to produce files without terminating 'cr', as well as empty files. (unless, of course you put extra code to remove last 'cr' when filing out, and add it back when filing in).. but once you start doing something like that, it leads exactly to what i want to prevent in a first place: extra code/logic to deal with inconsistency. -- Best regards, Igor Stasenko.
