Ruby | Set proper_subset?() function Last Updated : 12 Jul, 2025 Comments Improve Suggest changes Like Article Like Report The proper_subset? is an inbuilt method in Ruby that returns true if a set if a proper subset of another set. If it is not a proper subset, then it returns false. Syntax: s1.name.proper_subset?(s2.name) Parameters: The function does not takes any parameter. Return Value: It returns true if set s1 is a proper subset of s2, else it returns false. Example 1: Ruby # Ruby program to illustrate the proper_subset? method # requires the set require "set" s1 = Set[1, 2] s2 = Set[1, 2, 3] # proper_subset method used puts s1.proper_subset?(s2) Output: true Example 2: Ruby # Ruby program to illustrate the proper_subset? method # requires the set require "set" s1 = Set[1, 5] s2 = Set[1, 2, 3] # proper_subset? method used puts s1.proper_subset?(s2) Output: false Comment G gopaldave Follow 0 Improve G gopaldave Follow 0 Improve Article Tags : Ruby Ruby-Methods Ruby Set-class Explore Ruby Programming Language 4 min read OverviewRuby For Beginners 3 min read Ruby Programming Language (Introduction) 4 min read Comparison of Java with Other Programming Languages 4 min read Similarities and Differences between Ruby and C language 3 min read Similarities and Differences between Ruby and C++ 3 min read Environment Setup in Ruby 3 min read How to install Ruby on Linux? 2 min read How to install Ruby on Windows? 2 min read Interesting facts about Ruby Programming Language 2 min read BasicsRuby | Keywords 4 min read Ruby | Data Types 3 min read Ruby Basic Syntax 3 min read Hello World in Ruby 2 min read Ruby | Types of Variables 4 min read Global Variable in Ruby 2 min read Comments in Ruby 2 min read Ruby | Ranges 4 min read Ruby Literals 4 min read Ruby Directories 5 min read Ruby | Operators 11 min read Operator Precedence in Ruby 2 min read Operator Overloading in Ruby 5 min read Ruby | Pre-define Variables & Constants 5 min read Ruby | unless Statement and unless Modifier 2 min read Control StatementsRuby | Decision Making (if, if-else, if-else-if, ternary) | Set - 1 3 min read Ruby | Loops (for, while, do..while, until) 5 min read Ruby | Case Statement 3 min read Ruby | Control Flow Alteration 7 min read Ruby Break and Next Statement 2 min read Ruby redo and retry Statement 2 min read BEGIN and END Blocks In Ruby 2 min read File Handling in Ruby 4 min read MethodsRuby | Methods 3 min read Method Visibility in Ruby 3 min read Recursion in Ruby 4 min read Ruby Hook Methods 5 min read Ruby | Range Class Methods 5 min read The Initialize Method in Ruby 2 min read Ruby | Method overriding 2 min read Ruby Date and Time 3 min read OOP ConceptsObject-Oriented Programming in Ruby | Set 1 9 min read Object Oriented Programming in Ruby | Set-2 8 min read Ruby | Class & Object 4 min read Private Classes in Ruby 3 min read Freezing Objects | Ruby 2 min read Ruby | Inheritance 4 min read Polymorphism in Ruby 3 min read Ruby | Constructors 2 min read Ruby | Access Control 8 min read Ruby | Encapsulation 2 min read Ruby Mixins 3 min read Instance Variables in Ruby 3 min read Data Abstraction in Ruby 3 min read Ruby Static Members 3 min read ExceptionsRuby | Exceptions 4 min read Ruby | Exception handling 6 min read Catch and Throw Exception In Ruby 3 min read Raising Exceptions in Ruby 4 min read Ruby | Exception Handling in Threads | Set - 1 2 min read Ruby | Exception Class and its Methods 3 min read Ruby RegexRuby | Regular Expressions 3 min read Ruby Search and Replace 2 min read Ruby ClassesRuby | Float Class 7 min read Ruby | Integer Class 3 min read Ruby | Symbol Class 5 min read Ruby | Struct Class 5 min read Ruby | Dir Class and its methods 3 min read Ruby | MatchData Class 4 min read Ruby ModuleRuby | Module 4 min read Ruby | Comparable Module 3 min read Ruby | Math Module 4 min read Include v/s Extend in Ruby 2 min read Like