Keyword Examples

Question 1

BEGIN { puts “hi” }

Answer 1

BEGIN: Run this block when the script starts

Question 2

END { puts “hi” }

Answer 2

END: Run this block when the script is done

Question 3

alias X Y

Answer 3

alias: create another name for a function

Question 4

puts “Hello” and “Goodbye”

Answer 4

and: Logical and, but lower priority than &&

Question 5

begin end

Answer 5

begin: Start a block, usually for exceptions

Question 6

while true; break; end

Answer 6

break: break out of a loop right now

Question 7

case X; when Y; else; end

Answer 7

case: Case style conditional, like an if

Question 8

class x; end

Answer 8

class: Define a new class

Question 9

def X(); end

Answer 9

def: define a new function

Question 10

defined? Class == “constant”

Answer 10

defined?: Is this class/function/etc. defined already?

Question 11

(0..5).each do |x| puts x end

Answer 11

do: Create a block that maybe takes a parameter

Question 12

if X; else; end

Answer 12

else: Else conditional

Question 13

if X; elsif Y; else; end

Answer 13

elsif: Else if conditional

Question 14

begin end # many others

Answer 14

end: Ends blocks, functions, classes, everything

Question 15

begin ensure end

Answer 15

ensure: Run this code whether an exception happens or not

Question 16

for X in Y; end

Answer 16

for: For loop syntax. The .each syntax is preferred

Question 17

if X; end

Answer 17

if: If conditional

Question 18

for X in Y; end

Answer 18

in: In part of for-loops

Question 19

module X; end

Answer 19

module: Define a new module

Question 20

(0..5).each {|y| next }

Answer 20

next: skip to the next element of a .each iterator

Question 21

not true == false

Answer 21

not: logical not. But use ! instead

Question 22

puts “Hello” or “Goodbye”

Answer 22

or: Logical or.

Question 23

(0..5).each {|i| redo if i >2 }

Answer 23

redo: Rerun a code block exactly the same

Question 24

begin rescue X; end

Answer 24

rescue: Run this code if an exception happens

Question 25

(0..5).each {|i| retry if i > 2 }

Answer 25

retry: In a rescue clause, says to try the block again

Question 26

return X

Answer 26

return: Returns a value from a function

Question 27

defined? self == “self”

Answer 27

self: The current object, class, module

Question 28

super

Answer 28

super: The parent of this class

Question 29

if true then puts “hi” end

Answer 29

then: Can be used with if optionally

Question 30

undef X

Answer 30

undef: Remove a function definition from a class

Question 31

unless false then puts “not” end

Answer 31

unless: Inverse of if

Question 32

until false; end

Answer 32

until: Inverse of while, execute block as long as false

Question 33

case X; when Y; else; end

Answer 33

when: Part of case conditionals

Question 34

while true; end

Answer 34

while: while loop

Question 35

yield

Answer 35

yield: Pause and transfer control to the code block