#!/usr/bin/perl use strict; use warnings; $_ = 'oireqo````'; unless($_ =~ /^a/m){print "no match to a\n"} #no match to a if(!($_ =~ /^a/m)){print "no match to a\n"} #no match to a unless($_ =~ /^o/m){print "no match to a"}els…
循环控制:1.last 退出标签的语句块2.next 3.redo不推荐,循环次数不可控 4.goto不推荐.***************************************标签: 先定义一个 labellast|next|redo|goto label: last VS next 相当于C语言中的:last ==>breaknext ==>continue*************************************perl的continue语句:continue…
Undo/Redo for Qt Tree Model eryar@163.com Abstract. Qt contains a set of item view classes that use a model/view architecture to manage the relationship between data and the way it is presented to the user. The separation of functionality introduced…
1.Redo Log The redo log is a disk-based data structure used during crash recovery to correct data written by incomplete transactions. During normal operations, the redo log encodes requests to change table data that result from SQL statements or low-…
