This article is a list of reading cards for the English version of Ruby Method Karuta.Please see the manual for a detailed overview.
Ruby Method Karuta : English Instruction Manual - ESM アジャイル事業部 開発者ブログ
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- 001 : BasicObject#method_missing
- 002 : Object#public_send
- 003 : Object#send
- 004 : Object#is_a?
- 005 : Object#inspect
- 006 : Object#==
- 007 : Object#equal?
- 008 : Array#flatten
- 009 : Array#<<
- 010 : Array#filter
- 011 : Array#reject
- 012 : Array#size
- 013 : Array#join
- 014 : Array#include?
- 015 : Data.define
- 016 : Hash#compact
- 017 : Hash#merge
- 018 : Hash#transform_keys
- 019 : Hash#transform_values
- 020 : Method#source_location
- 021 : Method#curry
- 022 : Module#refine
- 023 : Integer#even?
- 024 : Integer#succ
- 025 : Proc#<<
- 026 : RubyVM::AbstractSyntaxTree.parse
- 027 : RubyVM::InstructionSequence.compile
- 028 : RubyVM::YJIT.enabled?
- 029 : String#encode
- 030 : String#split
- 031 : String#chomp
- 032 : String#concat
- 033 : String#empty?
- 034 : String#include?
- 035 : String#gsub
- 036 : String#size
- 037 : String#match?
- 038 : String#strip
- 039 : String#chars
- 040 : Symbol.all_symbols
- 041 : Comparable#clamp
- 042 : Enumerable#map
- 043 : Enumerable#lazy
- 044 : Enumerable#tally
- 045 : Enumerable#each_with_object
- 046 : GC.disable
- 047 : Kernel#binding
- 048 : Kernel#puts
- 049 : Math.#sqrt
- 050 : ObjectSpace.count_objects
001 : BasicObject#method_missing
Class
BasicObject
Argument
Undefined method name and variable-length arguments.
Return Value
Object
Description
Method called by Ruby interpreter when an invoked method is not defined.
Answer
BasicObject#method_missing
002 : Object#public_send
Class
Object
Argument
Method name and variable-length arguments
Return Value
Object
Description
Calls the method given as an argument and returns the execution result. Can only call public methods.
Answer
Object#public_send
003 : Object#send
Class
Object
Argument
Method name and variable-length arguments
Return Value
Object
Description
Calls the method given as an argument and returns the execution result. Can also call private methods.
Answer
Object#send
004 : Object#is_a?
Class
Object
Argument
Object to compare
Return Value
bool
Description
Determines whether self is an instance of the class given as argument or its subclasses.
Answer
Object#is_a?
005 : Object#inspect
Class
Object
Argument
None
Return Value
String
Description
Returns a string that represents the object in a human-readable format.
Answer
Object#inspect
↑Return to the "Next Card" button
006 : Object#==
Class
Object
Argument
Object to compare for equality
Return Value
bool
Description
Compares the value equality of objects.
Answer
Object#==
↑Return to the "Next Card" button
007 : Object#equal?
Class
Object
Argument
Object to compare for identity
Return Value
bool
Description
Compares the identity of objects.
Answer
Object#equal?
↑Return to the "Next Card" button
008 : Array#flatten
Class
Array
Argument
Depth of recursion for flattening
Return Value
Array
Description
Returns a new recursively flattened array of self.
Answer
Array#flatten
↑Return to the "Next Card" button
009 : Array#<<
Class
Array
Argument
Object to be added to the receiver
Return Value
self
Description
Destructively appends the argument to the end of self.
Answer
Array#<<
↑Return to the "Next Card" button
010 : Array#filter
Class
Array
Argument
Block for evaluating each element
Return Value
Array
Description
Returns an array containing all elements for which the block returns a truthy value.
Answer
Array#filter
↑Return to the "Next Card" button
011 : Array#reject
Class
Array
Argument
Block for evaluating each element
Return Value
Array
Description
Returns an array containing all elements for which the block returns a false or nil.
Answer
Array#reject
↑Return to the "Next Card" button
012 : Array#size
Class
Array
Argument
None
Return Value
Integer
Description
Returns the number of elements in the array.
Answer
Array#size
↑Return to the "Next Card" button
013 : Array#join
Class
Array
Argument
Optional string separator to be placed between elements
Return Value
String
Description
Returns a concatenated string of array elements.
Answer
Array#join
↑Return to the "Next Card" button
014 : Array#include?
Class
Array
Argument
Object to compare for value equality
Return Value
bool
Description
Determines whether the receiver has an element that is equal to the argument object using ==.
Answer
Array#include?
↑Return to the "Next Card" button
015 : Data.define
Class
Data
Argument
Variable-length arguments to define a value object class
Return Value
Class
Description
Defines a class for an immutable value object.
Answer
Data.define
↑Return to the "Next Card" button
016 : Hash#compact
Class
Hash
Argument
None
Return Value
Hash
Description
Returns a new Hash with nil values removed from self.
Answer
Hash#compact
017 : Hash#merge
Class
Hash
Argument
Hash to be merged
Return Value
Hash
Description
Returns the result of merging the contents of the Hash.
Answer
Hash#merge
↑Return to the "Next Card" button
018 : Hash#transform_keys
Class
Hash
Argument
Block for evaluating each element's key
Return Value
Hash
Description
Returns a Hash with all keys replaced by the result of calling the block on them.
Answer
Hash#transform_keys
019 : Hash#transform_values
Class
Hash
Argument
Block for evaluating each element's value
Return Value
Hash
Description
Returns a Hash with all values replaced by the result of calling the block on them.
Answer
Hash#transform_values
↑Return to the "Next Card" button
020 : Method#source_location
Class
Method
Argument
None
Return Value
Array
Description
Returns an array containing the source code's file name and line number.
Answer
Method#source_location
↑Return to the "Next Card" button
021 : Method#curry
Class
Method
Argument
Optional arity
Return Value
Proc
Description
Returns a curried Proc based on self.
Answer
Method#curry
↑Return to the "Next Card" button
022 : Module#refine
Class
Module
Argument
Class or module to be extended
Return Value
Module
Description
Extends the class specified by the argument with methods, etc. within the block.
Answer
Module#refine
↑Return to the "Next Card" button
023 : Integer#even?
Class
Integer
Argument
None
Return Value
bool
Description
Returns a boolean indicating whether the integer is even.
Answer
Integer#even?
↑Return to the "Next Card" button
024 : Integer#succ
Class
Integer
Argument
None
Return Value
Integer
Description
Returns the next integer of the receiver.
Answer
Integer#succ
↑Return to the "Next Card" button
025 : Proc#<<
Class
Proc
Argument
Object with call method
Return Value
Proc
Description
Returns a Proc composed of self and the argument.
Answer
Proc#<<
↑Return to the "Next Card" button
026 : RubyVM::AbstractSyntaxTree.parse
Class
RubyVM::AbstractSyntaxTree
Argument
Source code string
Return Value
RubyVM::AbstractSyntaxTree::Node
Description
Parses the string into an abstract syntax tree and returns the root node of the tree.
Answer
RubyVM::AbstractSyntaxTree.parse
↑Return to the "Next Card" button
027 : RubyVM::InstructionSequence.compile
Class
RubyVM::InstructionSequence
Argument
Source code string
Return Value
RubyVM::InstructionSequence
Description
Returns the iseq object of the specified Ruby source code in the argument.
Answer
RubyVM::InstructionSequence.compile
↑Return to the "Next Card" button
028 : RubyVM::YJIT.enabled?
Class
RubyVM::YJIT
Argument
None
Return Value
bool
Description
Determines whether YJIT is enabled.
Answer
RubyVM::YJIT.enabled?
↑Return to the "Next Card" button
029 : String#encode
Class
String
Argument
Target encoding
Return Value
String
Description
Returns a string by converting the receiver to the specified character encoding.
Answer
String#encode
↑Return to the "Next Card" button
030 : String#split
Class
String
Argument
Separator for splitting string
Return Value
Array
Description
Splits the string by the separator specified in the argument.
Answer
String#split
↑Return to the "Next Card" button
031 : String#chomp
Class
String
Argument
Optional newline character
Return Value
String
Description
Returns a new string with the newline character specified in the argument removed from the end of self.
Answer
String#chomp
↑Return to the "Next Card" button
032 : String#concat
Class
String
Argument
String to concatenate
Return Value
String
Description
Concatenates self with the string.
Answer
String#concat
↑Return to the "Next Card" button
033 : String#empty?
Class
String
Argument
None
Return Value
bool
Description
Determines whether the string is empty.
Answer
String#empty?
↑Return to the "Next Card" button
034 : String#include?
Class
String
Argument
String to search for
Return Value
bool
Description
Determines whether the argument string is included.
Answer
String#include?
↑Return to the "Next Card" button
035 : String#gsub
Class
String
Argument
Replacement pattern and replacement string
Return Value
String
Description
Replaces all strings that match the pattern.
Answer
String#gsub
↑Return to the "Next Card" button
036 : String#size
Class
String
Argument
None
Return Value
Integer
Description
Returns the length of the string.
Answer
String#size
↑Return to the "Next Card" button
037 : String#match?
Class
String
Argument
Regular expression or string as pattern
Return Value
bool
Description
Determines whether the string matches the pattern.
Answer
String#match?
↑Return to the "Next Card" button
038 : String#strip
Class
String
Argument
None
Return Value
String
Description
Removes leading and trailing whitespace characters.
Answer
String#strip
↑Return to the "Next Card" button
039 : String#chars
Class
String
Argument
None
Return Value
Array
Description
Returns an array of strings for each character in the string.
Answer
String#chars
↑Return to the "Next Card" button
040 : Symbol.all_symbols
Class
Symbol
Argument
None
Return Value
Array
Description
Returns an array of all defined symbol objects.
Answer
Symbol.all_symbols
↑Return to the "Next Card" button
041 : Comparable#clamp
Class
Comparable
Argument
Two values for lower and upper bounds or a Range
Return Value
Object
Description
Returns a value that falls within the specified lower and upper bounds.
Answer
Comparable#clamp
↑Return to the "Next Card" button
042 : Enumerable#map
Class
Enumerable
Argument
Block to evaluate for each element
Return Value
Array
Description
Returns an array containing the result of evaluating the block for each element.
Answer
Enumerable#map
↑Return to the "Next Card" button
043 : Enumerable#lazy
Class
Enumerable
Argument
None
Return Value
Enumerator::Lazy
Description
Returns a lazy enumerator that performs delayed evaluation of self.
Answer
Enumerable#lazy
↑Return to the "Next Card" button
044 : Enumerable#tally
Class
Enumerable
Argument
Optional hash to accumulate results
Return Value
Hash
Description
Returns a hash with the counted occurrences of each element in the enumerable.
Answer
Enumerable#tally
↑Return to the "Next Card" button
045 : Enumerable#each_with_object
Class
Enumerable
Argument
Initial value and block
Return Value
Object
Description
Iteratively passes the initial object and elements to the block and returns the initial object.
Answer
Enumerable#each_with_object
↑Return to the "Next Card" button
046 : GC.disable
Class
GC
Argument
None
Return Value
bool
Description
Disables garbage collection.
Answer
GC.disable
↑Return to the "Next Card" button
047 : Kernel#binding
Class
Kernel
Argument
None
Return Value
Binding
Description
Returns a Binding object containing environment information such as variables and methods.
Answer
Kernel#binding
↑Return to the "Next Card" button
048 : Kernel#puts
Class
Kernel
Argument
Any number of objects to output
Return Value
nil
Description
Outputs to standard output.
Answer
Kernel#puts
↑Return to the "Next Card" button
049 : Math.#sqrt
Class
Math
Argument
Positive real number
Return Value
Float
Description
Returns the square root of the argument.
Answer
Math.#sqrt
↑Return to the "Next Card" button
050 : ObjectSpace.count_objects
Class
ObjectSpace
Argument
Optional Hash
Return Value
Hash
Description
Returns a hash with the count of objects for each type.
Answer
ObjectSpace.count_objects
