文件操作 - demo_precalc.pl
返回文件管理
返回主菜单
删除本文件
文件: /usr/share/doc/perl-Parse-RecDescent-1.967009/demo/demo_precalc.pl
编辑文件内容
#!/usr/bin/perl -ws BEGIN { unless (-f "Calc.pm") { print "You first need to build Calc.pm.\n\n", "Try: perl -MParse::RecDescent - calc_grammar Calc\n", " or: demo_buildcalc.pl\n\n"; exit; } } use Parse::RecDescent; use Calc; sub evalop { # my (@list) = @{[@{$_[0]}]}; my (@list) = @{$_[0]}; my $val = shift(@list)->(); while (@list) { my ($op, $arg2) = splice @list, 0, 2; $op->($val,$arg2->()); } return $val; } my $parse = Calc->new() or die "bad grammar"; print "> "; while (<DATA>) { # FOR DEMO CHANGE TO: while (<DATA>) print $parse->main($_), "\n\n> "; } __DATA__ $x = 2 $y = 3 +1-1+1-1+1-1+1-1+1 7*7-6*8 121/(121/11)/121*11 1/(10-1/(1/(10-1))) $x * $y foreach $i (1..$y) $x = $x * 2 + $i $x
修改文件时间
将文件时间修改为当前时间的前一年
删除文件