Every java programmer hates NullPointerException. Indeed, any variable1 in java can take this special value of null, which indicates a lack of value in this variable. They are like landmines in your code; stomp upon one and boom! Your program is dead. Thus, programming in java is like wading …
This series of articles aims to explain why complicated type systems such as λC can be useful in practice, and how such use inevitably leads to the ability to formalize mathematics.
If you have been a software engineer and ever wondered "Why those PLT people invent all these fancy concepts …
Formalism eliminates falsehood; it does not lead to the truth.
Lists should be numbered from zero.
Tell the truth, not formal statements. Formal definitions are important, but they are not the essence of mathematics. What the notion really means is much more important than how it appears.
Motivation is important …
This is the ENS Entrance Exam 1995 Mathematics Written Part. Translated by Tony Beta Lambda.
Duration: 4 hours
In an informal way, an elementary function is a function defined on an open set of \({\mathbb R}\) or \({\mathbb C}\) and …
每一个学习数学的人都或多或少地接触过集合论. 所谓集合论，其研究对象就是集合和它们之间的“属于”关系. 在现代数学 …