Yuan Yijun (bbbush) wrote,
Yuan Yijun
bbbush

Morning reading (cont'd)

Continuations and advanced flow control
unstructured local-exit: goto; (Java)structured local-exit: exception handing; (Python)Another type of advanced flow control structure is a generator. Generators are functions that can generate a set of values, and return them one at a time as the function is called. A generator is able to "bookmark" its place in the current function to make programming easier....(Prolog)This sort of programming is called logic programming, because it allows you to state goals in terms of logical relationships and lets the computer do all of the legwork to find appropriate solutions to these logical relationships. The most important part of it, for our purposes, is the unique flow control that this sets up: backtracking. This means that at any point in the computation, if an appropriate value is not found in a particular variable, or a particular relationship among a group of variables is incorrect, the program can "back up" and assign a new value. This sort of programming simplifies a huge number of problem sets, especially in the area of smart systems....(Scheme)You could call these bookmarks "continue points" -- the place where the program will continue to if the advanced flow control structure is invoked. Or, more precisely, they are known as continuations. In fact, all of these control structures can be implemented using a single flow control function: call-with-current-continuation

坦率的说,不懂。:(

45 Minutes to a Moodle Education Server
The Moodle project, started by Martin Dougiamas in 1999, has delivered a most capable and feature rich tool for schools and educators. Moodle, also termed a Course Management System, is a web content tool currently used in over 150 countries.

国内的合作伙伴是谁呢


Apple and Dell: Business Models
小小地打击一把 Apple fans,不要小看 Dell,即使这几天 Dell 风声紧而 Apple 比较高调。喜欢这句话:
Check out Morningstar to confirm this!...



BTW, 昨天在 investopedia 链到了 www.fxcm.com,中国公司叫做“福汇”,然后炒了一把模拟外汇。赔了不少。Investopedia 这几天忙于开张 Advisor 站点,内容不咋地,却把本来的事情都撂下了,真是可惜。但愿它的 Advisor 能做出点什么,能反过来支持 主站。肖勇博士说,他炒了一个月,还赚了不少的。可是可是,外汇价格变动那么快,spread 又那么大...怎么可能赚钱吗。不过,我没有炒过股票,也许股票的 spread 也非常大?
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