Self-tutoring about regular expressions: the tutor mentions a use of the caret symbol, ^. It seems that, in regular expressions, “^” can mean “not” when it’s the first character inside of square brackets. For example, it seems that [^a-zA-Z] would …
Self-tutoring about PHP’s intval function: the tutor mentions a surprise. I was reading about PHP’s intval function today. It’s meant, as I understand, to convert a decimal number to an integer, by just keeping the integer part. Putting it in …
Self-tutoring about Windows: the tutor mentions a search he was pleased with. The other day I wanted to search a directory for files that weren’t jpg. I imagined keying “not .jpg” into the search bar, but that sounded perhaps too …
Self-tutoring about computer science: the tutor mentions the idea of a tuple. A tuple, as I understand, is a sequence of values that, together, mean something. The reason I’d say a tuple is a sequence is that the values are …
Self-tutoring about software engineering: the tutor mentions the distinction between functional and non-functional requirements. In software engineering, functional requirements describe the input and output of the software. Non-functional requirements may define such things as the operating system the software is …
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Self-tutoring about software modeling: the tutor mentions sequence diagrams. Sequence diagrams show the communication among objects within a system. Typically the activity starts from top left: the time axis is downward, while the “object axis” reaches rightward. Objects are represented …
Self-tutoring about computer science: the tutor mentions a distinction he heard decades ago. In computer science, inputs a function takes can be called parameters. If, by a function’s operation, one of its parameters gets changed in way that’s observable outside …
Computer science: pass by reference vs by value, part 1 Read more »
Self-tutoring about calling methods in object-oriented programming: the tutor mentions an error. Sometimes one might mean to chain methods such as new_ob=f1().f2().f3() but get an error like “the function f2 has no attribute f3”. Such an error might happen because …
Self-tutoring about software development models: the tutor mentions the waterfall model. In software development, a process model may also be referred to as a software development life cycle model. It generally refers to the steps of the development process itself. …
Self-tutoring about computer science: the tutor mentions the idea of a stub. In programming, a stub is a function that, when called, returns a value of the expected type so that the calling function can continue running. Being a stub …