What's New in Version 2

What’s New in Version 2

Version 2 of the Morphir IR schema introduces partial capitalization and a new module structure, representing a significant evolution from version 1.

Key Changes from Version 1

Partial Capitalization

Version 2 introduces capitalization for distribution, access control, and type-related tags:

Capitalized Tags

Distribution:

• "library" → "Library"

Access Control:

• "public" → "Public"
• "private" → "Private"

Type Tags:

• "variable" → "Variable"
• "reference" → "Reference"
• "tuple" → "Tuple"
• "record" → "Record"
• "extensible_record" → "ExtensibleRecord"
• "function" → "Function"
• "unit" → "Unit"

Type Specifications:

• "type_alias_specification" → "TypeAliasSpecification"
• "opaque_type_specification" → "OpaqueTypeSpecification"
• "custom_type_specification" → "CustomTypeSpecification"
• "derived_type_specification" → "DerivedTypeSpecification"

Type Definitions:

• "type_alias_definition" → "TypeAliasDefinition"
• "custom_type_definition" → "CustomTypeDefinition"

Unchanged (Lowercase) Tags

Value expressions remain lowercase:

• "apply", "lambda", "let_definition", "if_then_else", etc.

Patterns remain lowercase:

• "wildcard_pattern", "as_pattern", "constructor_pattern", etc.

Literals remain lowercase:

• "bool_literal", "string_literal", "whole_number_literal", etc.

New Module Structure

Version 2 changes how modules are represented in packages:

Version 1 Structure

{
  "modules": [
    {
      "name": [["my"], ["module"]],
      "def": ["public", { ... }]
    }
  ]
}

Version 2 Structure

{
  "modules": [
    [
      [["my"], ["module"]],
      {
        "access": "Public",
        "value": { ... }
      }
    ]
  ]
}

Changes:

• Modules are now represented as arrays instead of objects
• Structure changed from {"name": ..., "def": ...} to [modulePath, accessControlled]
• Access control uses the new AccessControlled wrapper with capitalized values

Access Control Wrapper

Version 2 introduces a structured AccessControlled wrapper:

AccessControlled:
  type: object
  required: ["access", "value"]
  properties:
    access:
      type: string
      enum: ["Public", "Private"]
    value:
      description: "The value being access controlled."

This provides a consistent way to manage visibility across types and values.

Benefits

Improved Clarity

• Capitalized type tags stand out more clearly in JSON structures
• Structured access control makes visibility explicit and consistent
• Array-based module structure is more compact and follows the pattern used elsewhere in the IR

Better Type Safety

The structured AccessControlled wrapper provides:

• Explicit access level declaration
• Type-safe representation
• Easier validation

Foundation for Version 3

Version 2 serves as a transition toward the fully capitalized format in version 3, making eventual migration easier.

Migration from Version 1

To migrate from version 1 to version 2:

1. Capitalize distribution tag: "library" → "Library"
2. Capitalize access control: "public" → "Public", "private" → "Private"
3. Update module structure: Convert {"name": ..., "def": ...} to array format
4. Capitalize all type tags: "variable" → "Variable", "reference" → "Reference", etc.
5. Capitalize type specification and definition tags

Looking Forward

While version 2 introduces important improvements, version 3 completes the capitalization by extending it to value expressions, patterns, and literals. For new projects, consider using version 3 directly for maximum consistency.

See Also

• Version 2 Overview
• Full Schema
• Migration to Version 3
• Version 1 Documentation