void A

1

• void A()
• cout ltlt hello ltlt endl
• int main()
• A()
• return(0)

2

• include ltfstream.hgt
• void A()
• int main()
• A()
• return(0)
• Saved this file as prog.cc

3

• include ltfstream.hgt
• void A()
• cout ltlt hello ltlt endl
• Saved this code in procA.cc

4

• include ltfstream.hgt
• void A()
• int main()
• A()
• return(0)
• I did not do an include in this example but
  simply compiled both CC files and linked
  together.
• g -c prog.cc
• g -c procA.cc o test.o
• g prog.o test.o o prog

5

• Separate compilation
• For every class have a separate .h file for the
  declarations.
• Have a separate .cc file for the class
  definitions.
• Have a separate .cc file for the main program or
  driver program.

6

• class A
• public
• A()
• int n
• Saved as classa.h

7

• include "classa.h"
• AA()
• n 42
• Saved as classa.cc

8

• include "classa.h"
• class B
• public
• B()
• A a,b
• B has a relationship with A
• Saved as classb.h

9

• include "classb.h"
• BB()
• a.n 17
• b.n 18
• Saved as classb.cc

10

• include ltfstream.hgt
• include "classb.h"
• int main()
• B x
• cout ltlt x.a.n ltlt endl
• Saved as prog.cc

11

• g -c Wall Werror classa.cc
• g -c Wall Werror classb.cc
• g -c Wall Werror prog.cc
• g -o progtest classa.o classb.o prog.o

12

• include ltfstream.hgt
• include "classb.h"
• include "classa.h"
• int main()
• B x
• cout ltlt x.a.n ltlt endl

13

• ifndef A_H
• define A_H
• class A
• public
• A()
• int n
• endif
• If a.h is not defined do everything up to it, if
  it is defined skip over to the endif

14

• Make Facility
• A UNIX command that looks for a file called
  Makefile or makefile.
• emacs Makefile
• Executes the first command in the file.
• Comments begin with
• ltstringgt
• lttabgt some command
• lttabgt some command

15

• Make Facility
• prog a.o b.o prog.o
• g -o prog a.o b.o prog.o
• prog is known as a target
• a.o b.o prog.o are known as dependencies
• When the target prog is called, it first checks
  to see if the dependencies are present, if they
  have a newer date then prog or if they are a
  target.

16

• Make Facility
• prog a.o b.o prog.o
• g -o prog a.o b.o prog.o
• a.o a.cc a.h
• g -c Wall Werror a.cc
• prog.o prog.cc b.h a.h
• g -c Wall Werror prog.cc
• b.o b.cc b.h
• g -c Wall Werror b.cc
• clean
• rm f .o prog

17

• Make Facility

make a.o make b.o make prog.o make clean
18

• Make Facility
• Edit a file a.h b.h a.cc b.cc prog.cc then by
  running make it will recompile and link.
• Macros can be used to put a string within a
  command.
• OPTIONS -c Wall Werror
• a.o a.cc a.h
• g (options) a.cc