软件在“洞”里（三） —— 读《计算思维史话》（十）

档案管理员模型，到底如何实现呢？这需要汇编语言：

Wheeler’s Initial Orders program was really the first practical realization of von Neumann’s hardware-software interface. It was also the first example of an assembly language, a programming language that used names instead of num�bers.

这意味着抽象更进一步：

Assembly languages constituted the next significant step up the hierarchy of software abstractions.

当然，“抽象”带来了翻译的需求：

To run an assembly language program, the assembly language first has to be translated into machine code. The need for such translation required the development of programs called assemblers that could perform the translation and produce machine code as out�put.

而且，还需要反复复用的可靠代码段（说白了就是抄作业）：

They therefore intro�duced the idea of a “library” of tested, debugged portions of programs that could be reused in other programs. These blocks of trusted code are now called subroutines.

再进一步，就是高级语言了：

However, Hopper had much larger ambitions than using just primitive abbreviations for the low-level opera�tions of assembly language. She began to investigate whether it was possible to write a program using expressions that more closely resembled every�day English.

She introduced the term compiler for the software system she created to translate programs written in A-0 to UNIVAC machine code...

再往后，就是FORTRAN和COBOL的出现了。