# constraint programming language

> programming language used for constraint programming

**Wikidata**: [Q28920160](https://www.wikidata.org/wiki/Q28920160)  
**Source**: https://4ort.xyz/entity/constraint-programming-language

## Summary
A constraint programming language is a programming language designed specifically for solving problems using constraint programming, where variables are subject to constraints that must be satisfied. These languages combine logic and constraint programming paradigms to express problems declaratively rather than procedurally.

## Key Facts
- Constraint programming languages are a subclass of programming languages
- They use the constraint programming paradigm as their primary programming approach
- Examples include Alice (created in 2000), Oz (created in 1991), and Alma-0 (created in 1997)
- Constraint Handling Rules was created in 1991 as a declarative, rule-based language
- Kaleidoscope is a constraint programming language that embeds constraints into an imperative object-oriented language
- MiniZinc is a constraint modeling language created in 2009
- These languages are related to constraint logic programming languages, which combine logic and constraint programming

## FAQs
### Q: What is the main purpose of a constraint programming language?
A: Constraint programming languages are designed to solve problems by expressing constraints that must be satisfied, allowing developers to describe what needs to be solved rather than how to solve it.

### Q: How do constraint programming languages differ from traditional programming languages?
A: Unlike traditional imperative languages that specify step-by-step procedures, constraint programming languages use a declarative approach where you define variables and constraints, and the system finds solutions that satisfy all constraints.

### Q: What are some examples of constraint programming languages?
A: Examples include Alice (2000), Oz (1991), Alma-0 (1997), Constraint Handling Rules (1991), Kaleidoscope (1994), and MiniZinc (2009).

## Why It Matters
Constraint programming languages represent a powerful paradigm for solving complex combinatorial problems that would be difficult or impossible to solve efficiently with traditional programming approaches. They are particularly valuable in scheduling, planning, resource allocation, and optimization problems where multiple constraints must be satisfied simultaneously. By allowing developers to express problems declaratively rather than procedurally, these languages enable more intuitive problem formulation and can leverage sophisticated constraint solving algorithms to find solutions automatically. This approach has found applications in logistics, manufacturing, telecommunications, and many other fields where finding optimal solutions under multiple constraints is critical. The ability to model real-world problems naturally and let the system handle the solution process makes constraint programming languages an essential tool in the computer science toolkit.

## Notable For
- Declarative problem-solving approach that separates problem specification from solution method
- Ability to handle complex combinatorial problems with multiple interdependent constraints
- Integration of logic programming and constraint satisfaction techniques
- Support for both complete and incomplete search strategies
- Applications in scheduling, planning, and optimization across diverse industries

## Body
### Classification and Paradigm
Constraint programming languages belong to the broader category of programming languages but are distinguished by their use of the constraint programming paradigm. This paradigm focuses on defining variables and constraints rather than specifying procedural steps to solve problems.

### Historical Development
The field emerged in the early 1990s with languages like Oz (1991) and Constraint Handling Rules (1991), followed by Alma-0 in 1997. These early languages established foundational concepts for constraint-based problem solving. Alice, created in 2000, represented a more modern approach to constraint programming.

### Language Examples and Features
Alice is a constraint programming language created in 2000, while Oz, created in 1991, combines functional and logic programming with constraints. Alma-0, from 1997, is a multi-paradigm language that includes constraint programming capabilities. Constraint Handling Rules, also from 1991, is specifically designed as a declarative, rule-based language for constraint programming.

### Specialized Approaches
Kaleidoscope takes a unique approach by embedding constraints into an imperative object-oriented language, created in 1994. MiniZinc, created in 2009, focuses specifically on constraint modeling, providing a high-level modeling language for constraint satisfaction and optimization problems.

### Applications and Use Cases
Constraint programming languages excel at solving scheduling problems, resource allocation, planning tasks, and other combinatorial optimization problems. They are particularly useful when problems involve multiple constraints that must be satisfied simultaneously, making them valuable in logistics, manufacturing, telecommunications, and other industries requiring complex decision-making under constraints.

## Schema Markup
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