concepts, not syntax


better living through organization
CS as managing complexity
  i.e. building, maintaining large, complex systems


software engineering == problem-solving to build big programs 
  tools
    editors
    debuggers
    profilers (used to analyze performance)
  design philosophies
    e.g. modularity (more later)
  testing methodologies
  ...


module
  clearly separated piece of a larger, complex system
  limited, well-defined interdependence w/ other modules


modules in the real world
  parts of a car, e.g. 
    engine, tires, radio, bumper, seats
  parts of my trip to Brooklyn, e.g. 
    walk to bus stop, bus to airport entrance, entrance to gate, gate to plane,
    first leg of flight, second leg of flight, etc.
  parts of your education process, e.g.
    major prerequisites, major core courses, senior project


modules in the software context at different levels
  a function
  related function definitions in a single source file
  a project w/ multiple source files
  programs grouped as a "suite," e.g. Microsoft Office, ClarisWorks


Why modularity?  Limited, well-defined interdependence means you can...
  develop a system's parts simultaneously.
  make changes to one module with a minimal, predictable impact on the rest of
    the system.
  locate bugs more easily.
  focus analysis (e.g. memory usage, speed) on one module 
  reuse modules in future systems.


modularity and real software
  MSVC
    editor, toolbars, file browser, debugger, compiler, linker
  Word
    editor, toolbars, file browser, spelling checker, printing
  Netscape 
    toolbars, file browser, image viewer, bookmark manager
  mail reader 
    editor, toolbars, file browser, address book

[Note common modules.  Consider advantages above.]


testing modules when rest of system is not complete
  stubs
  drivers


modularity at the file level
  source files
    .cpp for a group of related function definitions
  header files
    .h for each .cpp
    function declarations (prototypes), type definitions, constants


modularity in the build process
  preprocessing 
    #include headers, #define
  compiling 
    each .cpp to one .obj
  linking 
    multiple .obj and standard libraries to an executable


preprocessing:  the truth about #include (copy and paste)
  preprocessor replaces #include line w/ contents of header
  pointy braces vs. double quotes
    pointies for standard library headers (which you don't write)
      e.g. #include <iostream.h> 
    quotes for your own headers, located in same dir. as source files
      e.g. #include "myfunctions.h"


misc. notes

other common filename extensions 
  C++ source files:  .cc, .C (ack!)
  C++ header files:  .hh