3 ms·

Forth, Factor, and Io are languages that come to mind that have "no syntax". Ruby is certainly at the "more syntax" end of the spectrum. puts(("foo #{bar}

Forth, Factor, and Io are languages that come to mind that have "no syntax". Ruby is certainly at the "more syntax" end of the spectrum. puts(("foo #{bar} %s %s" % [bat, baz]) * 2.+(0b0010)) There are a huge number of syntax rules in that line.

kragen 18y ago
I count 23 in a PEG language without repetition. Here's an expanded version of your fragment that runs successfully: # from http://news.ycombinator.com/item?id=404609 bar = 3 bat = 4 baz = 5 puts(("foo #{bar} %s %s" % [bat, baz]) * 2.+(0b0010)) And here's a grammar for the subset of Ruby it uses: this <- 'A parsing expression grammar for a tiny subset of Ruby.'. copyright <- 'Written by Kragen Javier Sitaker 2008; in the public domain.'. program <- _ expr program / . noninfix <- inparens / call / constant / quasiquoted / list / name. expr <- infix / noninfix. inparens <- '('_ expr ')'_. call <- name '('_ commalist ')'_ / constant '.'_ methodname '('_ commalist ')'_. constant <- '0b' bits / digits. bits <- bit bits / bit _. bit <- '0' / '1'. digits <- digit digits / digit _. digit <- bit / '2' / '3' / '4' / '5' / '6' / '7' / '8' / '9'. quasiquoted <- '"' qqcontents '"'_. qqcontents <- !'#{' !'"' char qqcontents / interpolation qqcontents / . interpolation <- '#{' expr '}'. list <- '['_ commalist ']'_. commalist <- expr ','_ commalist / expr / . infix <- noninfix '%'_ expr / noninfix '*'_ expr / noninfix '='_ expr. _ <- sp _ / . sp <- ' ' / '\n' / comment. comment <- '#' commentchars '\n'. commentchars <- !'\n' char commentchars / . namechar <- 'b' / 'a' / 'r' / 't' / 'z' / 'p' / 'u' / 's'. name <- namechar name / namechar _. methodname <- '+'_ / name. I have tested it (in http://github.com/kragen/peg-bootstrap/tree/master/peg.md http://github.com/kragen/peg-bootstrap/tree/master/peg.md) and it seems to work for that fragment, although I haven't examined the parse tree to see if it's right. (Obviously the definition of namechar is wrong, and there's no $end token separating statements, and you can't call methods on things that aren't constants or self, etc.)

kragen 18y ago

I count 23 in a PEG language without repetition. Here's an expanded version of your fragment that runs successfully: # from http://news.ycombinator.com/item?id=404609 bar = 3 bat = 4 baz = 5 puts(("foo #{bar} %s %s" % [bat, baz]) * 2.+(0b0010)) And here's a grammar for the subset of Ruby it uses: this <- 'A parsing expression grammar for a tiny subset of Ruby.'. copyright <- 'Written by Kragen Javier Sitaker 2008; in the public domain.'. program <- _ expr program / . noninfix <- inparens / call / constant / quasiquoted / list / name. expr <- infix / noninfix. inparens <- '('_ expr ')'_. call <- name '('_ commalist ')'_ / constant '.'_ methodname '('_ commalist ')'_. constant <- '0b' bits / digits. bits <- bit bits / bit _. bit <- '0' / '1'. digits <- digit digits / digit _. digit <- bit / '2' / '3' / '4' / '5' / '6' / '7' / '8' / '9'. quasiquoted <- '"' qqcontents '"'_. qqcontents <- !'#{' !'"' char qqcontents / interpolation qqcontents / . interpolation <- '#{' expr '}'. list <- '['_ commalist ']'_. commalist <- expr ','_ commalist / expr / . infix <- noninfix '%'_ expr / noninfix '*'_ expr / noninfix '='_ expr. _ <- sp _ / . sp <- ' ' / '\n' / comment. comment <- '#' commentchars '\n'. commentchars <- !'\n' char commentchars / . namechar <- 'b' / 'a' / 'r' / 't' / 'z' / 'p' / 'u' / 's'. name <- namechar name / namechar _. methodname <- '+'_ / name. I have tested it (in http://github.com/kragen/peg-bootstrap/tree/master/peg.md http://github.com/kragen/peg-bootstrap/tree/master/peg.md) and it seems to work for that fragment, although I haven't examined the parse tree to see if it's right. (Obviously the definition of namechar is wrong, and there's no $end token separating statements, and you can't call methods on things that aren't constants or self, etc.)