Lisp-Ten Commandments
这十条戒律因该说是在进行Lisp编程时，需要引起格外注意的地方，否则便有可能引入错误。很有意思呢。。不太好翻译，还是英文原文表达的简洁易懂一些。所以摘录如下：
第一戒：
When recurring a list of atom, lat, ask two questions about it: (lat? l) and else.
When recurring on a number, n, ask two questions about it: (zero? n) and else.
When recurring on a list of S-expressions, l, ask three question about it: (null? l), (atom? ( car l)), and else.
第二戒：
Use cons to build lists.
第三戒：
When building a list, describe the first typical element, and then cons it onto the natural recursion.
第四戒：
Always change at least one argument while recurring.
When recurring on a list of atoms, lat, use (cdr lat).
When recurring on a number, n, use (sub1 n).
When recurring on a list of S-expressions, l, use (carl) and (cdr l) if neither (null? l) nor (atom? (carl)) are true.
第五戒：
When building a value with + ,always use 0 for the value of the terminating line, for adding 0 does not change the value of an addition.
When building a value with x, always use 1 for the value of the terminating line, for multiplying by 1 does not change the value of a multiplication.
When building a value with cons, always consider () for the value of the terminating line.
第六戒：
Simplify only after the function is correct.
第七戒：
Recur on the subparts that are of the same nature:
• On the sublists of a list.
• On the subexpressions of an arithmetic expression.
第八戒：
Use help functions to abstract from representation.
第九戒：
Abstract common patterns with a new function.
第十戒：
Build functions to collect more than one value at a time.
