When I read through Programming Perl, 2nd Edition, Page 51, something confuses me : sub newopen { my $path = shift; local *FH; #not my! open (FH, $path) || return undef; return *FH; } $fh = newopen('/etc/passwd'); My I know, why we are not recommenced to use my? So far, I cannot see anything will go wrong if we use...
Is there such a thing? I'm looking to translate something like "mfg"=>"manufacturing" or . I figure that I'd need a database of mappings. However, I can't seem to find one. I'm don't know a lot about lexical translations and the budget doesn't call for a lot of research, so are there any quick 'n dirty tools out there? ...
I'm looking at some older Perl code on Perl Monks to figure out programming with Win32::OLE and MS Word. Scattered throughout the code are variables with names like $MS::Word and the like, without a 'my' included in their declaration. After reading a bit on Google, I understand that these are called 'package variables' versus 'lexical va...
Hello guys I'm facing some problems on the lexical analysis of my compiler I had declared the following pointer char *words[29]={ "program", "label", "integer", "word", "char", "byte", "shortint", "logint", "real", "single", "double", "string", "boolean", "var", ...
Hey! I'm trying to help a friend in a college assignment, but i kind of forgot a lot of C an Lex. The thing is, we are trying to parse a HTML and a correspondent CSS file and add to a tag it's style. Eg: HTML <body> </body> CSS body{color:black;} modified HTML <body style="color:black;"> </body> All the regex are done and ...
Hi guys, sorry for such silly question, but I had argument with my pals about lexical analyze and we've decided to ask community. The question is: Whether the statement "int some_variable = ;" would be interpreted as invalid during the lexical analyze stage or during the syntax analyze stage in C grammar. Thanks ...
Why does this print 42: $answer = 42; $variable = "answer"; print ${$variable} . "\n"; but this doesn't: my $answer = 42; my $variable = "answer"; print ${$variable} . "\n"; ...
How to interpret the following xml element? xs:pattern value="[ !-~]*" ...
I'm implementing a small dictionary database where I'd like to do searches based on lexical/semantic similarity between them.. For example, beer has "sister words" such as soda, lemonade, wine, champagne each "different" in a "different direction" (in example: the first two are "moderate" versions of the idea of "beer", while the latte...
Starting in Perl 5.10, it is now possible to lexically scope the context variable $_, either explicitly as my $_; or in a given / when construct. Has anyone found good uses of the lexical $_? Does it make any constructs simpler / safer / faster? What about situations that it makes more complicated? Has the lexical $_ introduced any b...
I've seen two approaches to building parsers in Scala. The first is to extends from RegexParsers and define your won lexical patterns. The issue I see with this is that I don't really understand how it deals with keyword ambiguities. For example, if my keyword match the same pattern as idents, then it processes the keywords as idents....