forked from OSchip/llvm-project
				
			
		
			
				
	
	
		
			40 lines
		
	
	
		
			1.2 KiB
		
	
	
	
		
			Standard ML
		
	
	
	
			
		
		
	
	
			40 lines
		
	
	
		
			1.2 KiB
		
	
	
	
		
			Standard ML
		
	
	
	
(*===----------------------------------------------------------------------===
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 * Abstract Syntax Tree (aka Parse Tree)
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 *===----------------------------------------------------------------------===*)
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(* expr - Base type for all expression nodes. *)
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type expr =
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  (* variant for numeric literals like "1.0". *)
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  | Number of float
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  (* variant for referencing a variable, like "a". *)
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  | Variable of string
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  (* variant for a unary operator. *)
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  | Unary of char * expr
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  (* variant for a binary operator. *)
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  | Binary of char * expr * expr
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  (* variant for function calls. *)
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  | Call of string * expr array
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  (* variant for if/then/else. *)
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  | If of expr * expr * expr
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  (* variant for for/in. *)
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  | For of string * expr * expr * expr option * expr
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  (* variant for var/in. *)
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  | Var of (string * expr option) array * expr
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(* proto - This type represents the "prototype" for a function, which captures
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 * its name, and its argument names (thus implicitly the number of arguments the
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 * function takes). *)
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type proto =
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  | Prototype of string * string array
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  | BinOpPrototype of string * string array * int
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(* func - This type represents a function definition itself. *)
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type func = Function of proto * expr
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