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Posts Tagged ‘management’

Grace Hopper: Manager, after briefly being a programmer

November 21st, 2017 No comments

In popular mythology Grace Hopper is a programmer who wrote one of the first compilers. I think the reality is that Hopper did some programming, but quickly moved into management; a common career path for freshly minted PhDs and older people entering computing (Hopper was in her 40s when she started); her compiler management work occurred well after many other compilers had been written.

What is the evidence?

Hopper is closely associated with Cobol. There is a lot of evidence for at least 28 compilers in 1957, well before the first Cobol compiler (can a compiler written after the first 28 be called one of the first?)

The A-0 tool, which Hopper worked on as a programmer in 1951-52, has been called a compiler. However, the definition of Compile used sounds like today’s assembler and the definition of Assemble used sounds like today’s link-loader (also see: section 7 of Digital Computers – Advanced Coding Techniques for Hopper’s description of what A-2, a later version, did).

The ACM’s First Glossary of Programming Terminology, produced by a committee chaired by Hopper in June 1954.

Routine – a set of coded instructions arranged in proper sequence to direct the computer to perform a desired operation or series of operations. See also Subroutine.

Compiler (Compiling Routine) – an executive routine which, before the desired computation is started, translates a program expressed in pseudo-code into machine code (or into another pseudo-code for further translation by an interpreter). In accomplishing the translation, the compiler may be required to:

Assemble – to integrate the subroutines (supplied, selected, or generated) into the main routine, i.e., to:

    Adapt – to specialize to the task at hand by means of preset parameters.

    Orient – to change relative and symbolic addresses to absolute form.

    Incorporate – to place in storage.

Hopper’s name is associated with work on the MATH-MATIC and ARITH-MATIC Systems, but her name does not appear in the list of people who wrote the manual in 1957. A programmer working on these systems is likely to have been involved in producing the manual.

After the A-0 work, all of Hopper’s papers relate to talks she gave, committees she sat on and teams she led, i.e., the profile of a manager.

sizeof i++

November 11th, 2009 No comments

It is quite common for coding guideline documents to contain at least one guideline recommending against the use of a construct that developers very rarely use, for instance: “The operand of the sizeof operator shall not contain side-effects.”

... sizeof i++; // Is the author expecting i to be incremented?

Why do such recommendations get incorporated into guideline documents? The obvious answer is that their author(s) are unaware of actual developer usage and believe the recommendation has value.

I have heard people claim that such recommendations are harmless, after all the adherence cost is minimal. Besides, the fact that code very likely already adheres to it will increase the “pass” rate for the set of guidelines the first time developers check their code. However, such guidelines unjustifiably increase peoples confidence in software (as measured by the number of guidelines adhered to). They not only fail to add value to a set of coding guidelines, but their presence could result in the probity of the other guidelines being questioned.

I continue to be surprised by the amount of resistance encountered by my attempts to have the “sizeof” guideline removed from, or not included in, a set of coding guidelines. In the case of an existing set of guidelines there is obviously a resistance to change, but I have not yet managed to extract a single promise to consider removing the guideline in a future revision.

People seem unimpressed by the amount of source code I have searched in a vain attempt to find a violation of the “sizeof” guideline, but they often have some vague memory of having seen an instance of this elusive usage. My questions asking after the name of the source file, the name of the program, the name of the project, or simply the name of the company they were working for at the time are greeted with uncertainty. Perhaps the only instance they have seen is in the example underneath the text of the recommendation? Growls and pointed looks.

Another factor is existing practice, if it appears in other guideline documents it must have some benefit. People don’t want to go out on a limb. Besides, basing decisions on measurement of source code, who does that these days?

Whatever else might be said about the “sizeof” guideline, it does make a great example that developers can use to regale management.

Superior tone: Less experienced developers
Earnest voice: don’t always have a complete understanding of C/C++
Shock: They make the mistake of thinking
Talking very fast: that the code sizeof i++
Incredulity: will cause i to be incremented!
Emphasis: This guideline
Relieved voice: ensures that this mistake os warned about.

This article originally appeared in an earlier blog of mine which I did not keep up.