Exercise 22

Question 1

puts

Answer 1

put string

Prints a string onto the screen. Includes newline character at the end.

Question 2

print

Answer 2

Prints a string onto the screen.

Doesn’t include newline character at the end.

Question 3

””

Answer 3

double quotes.

Tell Ruby to interpret what’s within the characters as Ruby code.

Question 4

#

Answer 4

octothorpe or pound symbol. Turns lines of code into comments.

Question 5

{}

Answer 5

format activator. Tells Ruby to interpolate its contents as code

Question 6

variable

Answer 6

A name that holds a piece of information.

Question 7

+

Answer 7

plus operator. Used for addition. Can add numbers or combine strings.

Question 8

-

Answer 8

minus operator. Used for subtraction.

Question 9

/

Answer 9

slash operator. Used for division.

Question 10

*

Answer 10

asterik operator.

Used for multiplication. Can multiply numbers or strings. Two asteriks together will find a number’s exponent.

Question 11

%

Answer 11

percent.

Can be used as a modulus operator. It finds the remainder after division.

Question 12

*>

Answer 12

less than.

Comparison operator. Checks to see if an item is less than another.

Question 13

>

Answer 13

greater than. Comparison operator. Checks to see if an item is greater than another.

Question 14

<=

Answer 14

less than or equal to. Comparison operator. Checks if an item is less than another. Also checksif the item is equal to the other.

Question 15

=>

Answer 15

greater than or equal to. Comparison operator. Checks if an item is greater than another.Also checks if the item is equal to the other.

Question 16

=

Answer 16

assignment operator.

Assigns values to a variable.

Question 17

.

Answer 17

decimal.

Turns numbers into floats. Also used to call methods on variables.

Question 18

”

Answer 18

single quotes.

Create strings. Won’t do string interpolation.

Question 19

true

Answer 19

boolean value.

Question 20

false

Answer 20

boolean value.

Question 21

%q{}

Answer 21

Creates a string.

Doesn’t interpolate variable names or other Ruby code.

Question 22

’’’

Answer 22

triple single quotes.

Used for multi-line strings. Doesn’t interpolate variable names or other Ruby code.

Question 23

gets

Answer 23

get string.

Records string input from the user.

Question 24

.chomp

Answer 24

A method.

Removes newline character at the end of a string.

Question 25

open(filename) 

Answer 25

A method.  Takes filename as parameter and returns file object.

Question 26

\n  

Answer 26

newline.   Whitespace character, aka an Escape Sequence.  Separates paragraphs from each other.

Question 27

\t 

Answer 27

tab.  Whitespace character, aka an Escape Sequence.  Indents.

Question 28

\\ 

Answer 28

backward slash.  Escape sequence.  Tells Ruby to print a single backslash inside a string.

Question 29

() 

Answer 29

Parentheses.  Can be used to enter parameters.

Question 30

.to_i 

Answer 30

A method.  Converts string to an integer.

Question 31

.to_f 

Answer 31

A method.  Converts fixnum to a float.

Question 32

ARGV  

Answer 32

Argument variable.  Tells Ruby to take variables, unpack them, and assign values given by the user to the variable names assigned to ARGV.

Question 33

$stdin 

Answer 33

standard input.  Used instead of gets when we enter arguments into the command line.

Question 34

"""  

Answer 34

triple double quotes. Used for multi-line strings.  Interpolates code.

Question 35

read

Answer 35

A method.  Used on file objects.  Returns a file's contents.

Question 36

.close 

Answer 36

A method.  Used on file objects.  Closes file.

Question 37

ARGV.first 

Answer 37

Used when entering only one argument into the command line.

Question 38

.truncate() 

Answer 38

A method.  When used on file objects, it truncates existing contents to zero length.

Question 39

.length  

Answer 39

A string method that returns the length of the string.

Question 40

.exist?  

Answer 40

Returns true if a file exists.  Returns false if it doesn't.

Question 41

w  

Answer 41

"Write-Only" mode.  Passed as an extra parameter to open(filename).  Automatically truncates existing file to zero length, or creates a new file for writing.

Question 42

.write 

Answer 42

File object method.  Writes a given string into a file.

Question 43

def  

Answer 43

Keyword used to denote a method's definition.

Question 44

end  

Answer 44

Keyword that denotes the end of a method's definition.

Question 45

*args  

Answer 45

Creates a list of arguments, used for multiple arguments.

Question 46

.seek 

Answer 46

Looks for a specific place in the file's contents.

Question 47

+=  

Answer 47

Positive increment.  Adds to existing variable value.  (variable +=  1 is the same as variable = variable + 1 )

Question 48

return  

Answer 48

Gets data or variables back from the method.  We can use puts before calling a method, and it will actually print out the return value in our script.