Implement Type System

[singlerr]

Reconstruct AST model

Current AST lacks sufficient information since it tries to cover all syntax. This was mainly caused by limitation of YACC/LEX grammar syntax.
We must transform AST model to be more suitable to type system

#6

Implement Type inference using unification algorithm

See Making a language tutorial

[Copilot]

Pull request overview

This PR implements a type system for the transpiler by reconstructing the AST model and introducing type inference capabilities using a unification algorithm. The changes replace the existing simplified type system with a more sophisticated approach based on Hindley-Milner type inference.

Changes:

• Introduced new type system infrastructure with type variables, constraints, and unification
• Added efficient-and-flexible array (ENA) data structure implementation for managing type variables
• Integrated supporting data structures (btree, hamt, vec) for type system operations

Reviewed changes

Copilot reviewed 35 out of 38 changed files in this pull request and generated 1 comment.

Show a summary per file

File	Description
src/transpiler/type/inference.h	Defines error types for type inference operations
src/transpiler/type/base.h	Core type system structures including types, constraints, and inference state
src/transpiler/type.h	Removed old simplified type system
src/transpiler/type.c	Removed old type system implementation
src/transpiler/symrec.h	Updated to reference new common types header and reformatted
src/transpiler/symrec.c	Removed symbol table and type management functions
src/transpiler/ena/*.{c,h}	Added unification table implementation for type inference
src/transpiler/data/vec/*.{c,h}	Added dynamic vector data structure
src/transpiler/data/hamt/*.{c,h}	Added hash array-mapped trie implementation
src/transpiler/data/btree/*.{c,h}	Added B-tree implementation
src/transpiler/data/Makefile	Build configuration for data structures
src/transpiler/ast_typing.{h,c}	Removed old type compatibility checking logic
src/transpiler/ast_sqz.h	Updated includes and reformatted
src/transpiler/ast_sem.h	Updated includes and reformatted
src/transpiler/ast.h	Added node_id type and reformatted
src/transpiler/Makefile	Updated to include ena and data subdirectories

Comments suppressed due to low confidence (4)

src/transpiler/type/inference.h:1

• The enum value 'OK' is ambiguous and may conflict with common system macros. Consider renaming to 'TYPE_ERROR_OK' or 'TYPE_OK' for clarity and to avoid potential naming collisions.
  src/transpiler/type/base.h:1
• The enum value 'UNEXPECTED_FUN' is duplicated between both 'provenance_tag' (line 54) and 'type_error_tag' (line 104). This creates ambiguity. Consider using unique prefixes like 'PROVENANCE_UNEXPECTED_FUN' and 'TYPE_ERROR_UNEXPECTED_FUN' to distinguish them.
  src/transpiler/symrec.c:1
• The file now only contains includes with no function implementations. If all implementations have been removed, consider removing this file entirely rather than leaving an empty implementation file.
  src/transpiler/data/hamt/src/uh.c:1
• Corrected spelling of 'importatnt' to 'important'.

#include "uh.h"

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