Server IP : 85.214.239.14 / Your IP : 3.147.82.108 Web Server : Apache/2.4.62 (Debian) System : Linux h2886529.stratoserver.net 4.9.0 #1 SMP Tue Jan 9 19:45:01 MSK 2024 x86_64 User : www-data ( 33) PHP Version : 7.4.18 Disable Function : pcntl_alarm,pcntl_fork,pcntl_waitpid,pcntl_wait,pcntl_wifexited,pcntl_wifstopped,pcntl_wifsignaled,pcntl_wifcontinued,pcntl_wexitstatus,pcntl_wtermsig,pcntl_wstopsig,pcntl_signal,pcntl_signal_get_handler,pcntl_signal_dispatch,pcntl_get_last_error,pcntl_strerror,pcntl_sigprocmask,pcntl_sigwaitinfo,pcntl_sigtimedwait,pcntl_exec,pcntl_getpriority,pcntl_setpriority,pcntl_async_signals,pcntl_unshare, MySQL : OFF | cURL : OFF | WGET : ON | Perl : ON | Python : ON | Sudo : ON | Pkexec : OFF Directory : /usr/share/doc/libparse-recdescent-perl/examples/ |
Upload File : |
#!/usr/bin/perl -sw # PARSE LOGICAL EXPRESSIONS TO A "list of lists" PARSE TREE sub printtree { print " " x $_[0]; print "$_[1]:\n"; foreach ( @_[2..$#_] ) { if (ref($_)) { printtree($_[0]+1,@$_); } else { print " " x $_[0], "$_\n" } } print "\n"; } use Parse::RecDescent; $RD_AUTOACTION = q{ [@item] }; $grammar = q{ expr : disj disj : conj 'or' disj | conj conj : unary 'and' conj | unary unary : 'not' atom | '(' expr ')' | atom atom : /[a-z]+/i }; $parse = new Parse::RecDescent ($grammar); while (<DATA>) { my $tree = $parse->expr($_); printtree(0,@$tree) if $tree; } __DATA__ a and b and not c (c or d) and f