bp@cs.hull.ac.uk (Barry Prescott) (05/25/91)
I have to produce a lexical analyser in Smalltalk-80 for an abstract document editor. I thought I could reuse the Smalltalk class 'Scanner', but it looks like its tuned for scanning Smalltalk. Is it worth my while useing this code, or should I start from scratch? Has anyone else done this? I am using ParcPlace smalltalk v2.2 Thanks in advance, -- Barry Prescott, Hypertext/CASE Systems Group, University of Hull, Hull, UK INTERNET: bp@cs.hull.ac.uk Telephone: +44 482 465016 [] JANET: bp@uk.ac.hull.cs Fax: +44 482 466666 / UUCP: ..!ukc!hu-cs!bp []<-----
sdl@d74sun.lyra.mitre.org (Steven D. Litvinchouk) (05/26/91)
In article <22808.9105242206@olympus.cs.hull.ac.uk> bp@cs.hull.ac.uk (Barry Prescott) writes: > I have to produce a lexical analyser in Smalltalk-80 for an abstract > document editor. I thought I could reuse the Smalltalk class > 'Scanner', but it looks like its tuned for scanning Smalltalk. > > Is it worth my while useing this code, or should I start from > scratch? Has anyone else done this? I once had to write a scanner for an ASCII representation of "DIANA" (an intermediate notation employed by Ada compilers and other Ada tools). I defined DIANAScanner as a subclass of Scanner. I only had to override four or five methods, including one to fix up the typeTable. So for me it was worth it to reuse Scanner, because I was able to reuse the same overall OO architecture of the class. However, it was also apparent to me that some of Scanner's existing methods were fairly long (by Smalltalk standards), and so my overrides of those methods were also fairly long. (I basically had to copy all the code and make small mods to it.) -- Steven Litvintchouk MITRE Corporation Burlington Road Bedford, MA 01730 (617)271-7753 ARPA: sdl@mbunix.mitre.org UUCP: ...{att,decvax,genrad,necntc,ll-xn,philabs,utzoo}!linus!sdl "Where does he get those wonderful toys?"