636c49e9df
- Add isOwn field to Symbol for tracking own T declarations - Reinitialization after move: assigning to a moved variable removes it from movedVars - Move tracking in let/var initialization: var b: own Box = a moves a - Move tracking in assignment: x = y moves y if y is own T - Move tracking in return: return x moves x if x is own T - Expand borrow_test.nim to 10 tests (all passing)
46 lines
1.0 KiB
Nim
46 lines
1.0 KiB
Nim
import std/tables
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import types, ast, source_location
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type
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SymbolKind* = enum
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skVar
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skFunc
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skType
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skConst
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skModule
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Symbol* = ref object
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kind*: SymbolKind
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name*: string
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typ*: Type
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decl*: Decl ## optional back-reference to AST decl
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isMutable*: bool
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isPublic*: bool
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isOwn*: bool ## true if declared as own T
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Scope* = ref object
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parent*: Scope
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table*: Table[string, Symbol] ## O(1) lookup via hash table
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proc newScope*(parent: Scope = nil): Scope =
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result = Scope(parent: parent)
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proc define*(scope: Scope, sym: Symbol): bool =
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## Returns false if name already exists in this scope
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if scope.table.hasKey(sym.name):
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return false
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scope.table[sym.name] = sym
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return true
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proc lookup*(scope: Scope, name: string): Symbol =
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var cur = scope
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while cur != nil:
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if cur.table.hasKey(name):
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return cur.table[name]
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cur = cur.parent
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return nil
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proc lookupLocal*(scope: Scope, name: string): Symbol =
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if scope.table.hasKey(name):
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return scope.table[name]
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return nil |