Comp Sci Ch 7 Ch 8 Flashcards
What is a function?
grouping of statements for repeatedly used operations
- a named list of statements
function definition vs call
definition - function’s type, name, parameters and block of statements
call- name and arguments
what is a return statement?
and what is void
can return only one
void function does not return
what is a parameter? and how does it look
a function input specified in a function definition
type and name
what is an argument?
a value provided to a functions parameter during a call
what are multiple parameters separated by
comma
order in which program should run when declaring functions
declare before main and then call in main (this one better)
OR
declare header (but instead of {, have ;) before main then call in main and then define after main
what is modular development?
dividing program into separate modules that can be developed and tested separately and then integrated into one single program
what is incremental development?
a process of writing, compiling and testing a small amount of code
what is a function stub?
a function definition that statements have not been written
-write the header, braces, and return 0
-because just want it to complie
what is unit testing?
process of individually testing a small part or unit of a program
what is a test bench?
test harness
a separate program whose purpose is to check that a function returns
what is a test vector?
each unique set of input values
how would you use a test vector?
cout what you are testing, what you expect and what you got by calling function with literals to test
what predefined function can you use to test a function what does it do and what do you have to include
include <cassert></cassert>
assert( functionName(literal arguments) == what you should get)
- it exits program if input expression is false and tell you the line and expression
what is the one function you will never call
main
difference between type functions and void
types return a value
void functions cout or update values but do not return
a variable you declare in a function…
does not exist outside that function
what is the common method to swap variables
temp variable
what is scope?
the name of a defined variable or function item is only visible to a part of a program
what is a global variable? and why should we use very little
variable declared outside any function and reaches into functions
- because of naming and updates so it is limited to const variables
what is a preprocessor
a tool that scans the file top to bottom looking for any lines that begin with #
what is # called
hash symbol
what does a line with # do
directs preprocessor to modify the file in some way before compilation continues
what is #include called?
preprocessor directive
- directs compiler to replace that line by the contents of the given file name
including a file with “” vs <>
””- preprocessor to look for the file in some directory/folder as the including file
<>- looks in the system’s standard library folder/directory
adding .h to the back of a file name under “” does..
any file that will be included in another file
what is a stack frame?
each function creates a new set of local variable
what does a return do to local variables
discards them
what is a parameter
into that a functions needs to do its job and tends to get it from another function
how can we share info between main and other functions
with parameters
what is a pass by value parameter
communicates from other function a value or piece of data
- can communicate into but not out (needs a return)
- only allows one piece of into to exit out
what is a pass by reference parameter?
communicates info regarding the location of a piece of data
-passes in the memory address of where info it so that function can go find it
- both in and out of function
what is a const pass by reference parameter
- still shares location but is limited to only read
- just read only to that function that has it as a const parameter
we are default to what parameter except when..
pass by value except when:
1- need to communicate more than one piece of info to the calling function…returning more than one
2- if parameter is large data type ( string or vector of 10 elements or more)
what is the main difference between pass by value and reference parameters
value - passes in a value and
needs a return statement
reference- passes in a location address and do not need a return statement because retuning more than one ( so use void functions)
what type of function can use reference parameters
void because these do not return
how a void function with a reference parameter works and is called
call 1st to update values
then output the arguments that correspond to the reference parameters
simple steps to make a function
- what type needs to be returned
- meaningful name
- figure out parameters - what does function need from main (or the calling function)
- ask if need pass by reference parameters - based on how many to return or if a large data type
- body and return (if applicable)
- call it - void with no cout, later cout the arguments called that correspond to the reference parameters - return type, with cout
how to call a function with reference parameters
you only need the & in the definition function
- when calling put the variables you created in the call
- then cout those variables that correspond to the reference ones in the function
