v2.transformer #

fn Transformer.new(files []ast.File, env &types.Environment) &Transformer

fn Transformer.new_with_pref(files []ast.File, env &types.Environment, p &pref.Preferences) &Transformer

struct Transformer {
mut:
	pref &pref.Preferences = unsafe { nil }
	env  &types.Environment
	// Current scope for type lookups (walks up scope chain)
	scope &types.Scope = unsafe { nil }
	// Function root scope for registering transformer-created temp variables
	// This allows cleanc to look up temp variable types from the environment
	fn_root_scope &types.Scope = unsafe { nil }
	// Current module for scope lookups
	cur_module string
	// Temp variable counter for desugaring
	temp_counter int
	// Counter for synthesized positions (uses negative values to avoid collision)
	synth_pos_counter int = -1
	// Track needed auto-generated str functions (type_name -> elem_type for arrays)
	needed_str_fns map[string]string
	// Track needed auto-generated array helper functions
	needed_array_contains_fns   map[string]ArrayMethodInfo
	needed_array_index_fns      map[string]ArrayMethodInfo
	needed_array_last_index_fns map[string]ArrayMethodInfo
	// Current function's return type name (for sum type wrapping in returns)
	cur_fn_ret_type_name string
	// Tracks whether the current function returns Option/Result.
	// Some transformations use this to avoid wrapping plain sumtype returns.
	cur_fn_returns_option bool
	cur_fn_returns_result bool
	// When set, match branch values should be wrapped in this sum type
	// (used when a match expression is returned from a function with sum type return)
	sumtype_return_wrap string
	// Smart cast context stack - supports nested smart casts
	smartcast_stack []SmartcastContext
	// Functions that should be elided (conditional compilation, e.g. @[if verbose ?])
	elided_fns map[string]bool
	// Runtime const initializers grouped by module, preserving module discovery order.
	runtime_const_inits_by_mod map[string][]RuntimeConstInit
	runtime_const_modules      []string
	runtime_const_init_fn_name map[string]string
	// Resolved replacement for compile-time pseudo variable @VMODROOT.
	comptime_vmodroot string
	// Statements generated by expression-level expansions (e.g. filter/map)
	// that must be hoisted before the current statement in transform_stmts.
	pending_stmts []ast.Stmt
	// When true, skip lowering value-position IfExpr to temp variable.
	// Set during contexts that already handle IfExpr RHS (e.g. decl_assign).
	skip_if_value_lowering bool
	// For native backends: map interface variable names to their concrete type names.
	// When we see `shape1 := Shape(rect)`, record shape1 → "Rectangle".
	// Used to rewrite interface method calls to direct concrete calls.
	interface_concrete_types map[string]string
	// Track needed auto-generated sort comparator functions
	needed_sort_fns     map[string]SortComparatorInfo
	needed_enum_str_fns map[string]types.Enum
	// Override array element types for variables whose checker-inferred type is wrong
	// (e.g. .map(fn_name) typed as []voidptr instead of []ReturnType)
	array_elem_type_overrides map[string]string
	// File set for resolving positions to line numbers (for assert messages)
	file_set &token.FileSet = unsafe { nil }
	// Current file and function name (for assert messages)
	cur_file_name   string
	cur_fn_name_str string
	// @[live] hot code reloading: function names and source file
	live_fns         []LiveFn
	live_source_file string
}

Transformer performs AST-level transformations to simplify and normalize code before codegen. This avoids duplicating transformation logic across multiple backends (SSA, cleanc, etc.)

fn (mut t Transformer) set_file_set(fs &token.FileSet)

fn (mut t Transformer) transform_files(files []ast.File) []ast.File

transform_files transforms all files and returns transformed copies