ISO/IEC 20619:2023

Overview

ISO/IEC 20619:2023 is the international standard defining the C# specification suite, published by ISO and IEC. This first edition consolidates key components that specify the syntax, semantics, and library requirements for the widely used C# programming language. Developed in collaboration with Ecma International, this suite provides a structured framework for consistent implementation of C#. By referencing the latest Ecma standards, ISO/IEC 20619:2023 ensures alignment with evolving technology while maintaining stability for developers and organizations adopting the language.

This standard is essential for software developers, tool vendors, and platform implementers aiming to develop or support C# applications with conformance to internationally recognized language specifications.

Key Topics

• C# Language Specification
  Defines the syntax, semantics, and pre-processing directives of the C# language, including compulsory and optional features. This component ensures consistent interpretation of C# code and seamless interoperability across implementations.

• C# Library Specification
  Establishes the required class libraries usable in C# programs, drawn from ECMA-335 Partition IV, while focusing on the subset mandated for C# by ECMA-334. This foundation enables robust application development with standardized APIs and data types.

• Normative References
  The specification suite incorporates:

  • ECMA-334 - C# Language Specification
  • ECMA-335 Partition IV - Common Language Infrastructure (CLI): Profiles and Libraries

• Modular Structure
  The suite aggregates components via normative and informative references, meaning the suite itself changes only when components are added or removed, not merely through updates to individual specifications.

Applications

• Software Development
  Provides a definitive reference for designing C# compilers, interpreters, and development tools standardized on international guidelines.

• Cross-Platform Frameworks
  Helps ensure that C# implementations maintain consistent behavior across diverse operating systems and runtime environments.

• Education and Certification
  Standards-based curricula and certification programs can rely on ISO/IEC 20619:2023 to teach and evaluate proficiency in C# programming aligned with current best practices.

• Enterprise and Government Use
  Organizations requiring standardized IT development practices can mandate compliance with this suite to guarantee consistent quality and maintainability of C# applications.

Related Standards

• ECMA-334: C# Language Specification
  Detailed technical document specifying C# language syntax and semantics.

• ECMA-335: Common Language Infrastructure (CLI)
  Provides the comprehensive framework for language integration, including profiles and libraries relevant to C#.

• ECMA TR/84: CLI Information Derived from Partition IV XML File
  Technical report offering supplemental information about the CLI profiles and libraries used within the .NET ecosystem.

Practical Value

ISO/IEC 20619:2023 plays a critical role in unifying the C# language’s implementation globally. It fosters interoperability, reduces ambiguity in compiler development, and facilitates the evolution of the language within a consistent international framework. Developers and organizations leveraging this standard benefit from:

• Stable language foundation compatible with modern IT infrastructure
• Reduced risk of incompatibility between software components
• Streamlined development processes guided by clear normative references
• Confidence in adopting C# for large-scale and cross-industry solutions

By aligning practices with ISO/IEC 20619:2023, stakeholders contribute to a cohesive C# ecosystem benefiting the wider programming community.