-(* Goalfile evaluation
+(* Goalfile Abstract Syntax Tree
* Copyright (C) 2019 Richard W.M. Jones
* Copyright (C) 2019 Red Hat Inc.
*
* 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
*)
+open Printf
+
open Utils
-let rec evaluate_targets env exprs =
- List.iter (evaluate_target env) exprs
+let rec to_constant env = function
+ | Ast.EConstant (loc, c) -> c
-and evaluate_target env = function
- | Ast.EGoal _ -> assert false
+ | EVar (loc, name) ->
+ let expr = Ast.getvar env loc name in
+ to_constant env expr
- (* This could be an instruction to call a goal, or it
- * could be a tactic.
- *)
- | Ast.ECall (loc, "file", [filename]) (* XXX define tactics! *) ->
- (* All parameters of tactics must be simple expressions (strings,
- * in future booleans, numbers, etc).
- *)
- let args = [filename] in
- let args = List.map (simplify env) args in
- run_goal_for_tactic loc env "file" args
+ | ESubsts (loc, str) ->
+ CString (substitute env loc str)
- | Ast.ECall (loc, "file", _) ->
- failwithf "%a: file tactic called with wrong number of parameters"
+ | EList (loc, _) ->
+ failwithf "%a: list found where constant expression expected"
Ast.string_loc loc
- | Ast.ECall (loc, name, args) ->
- let expr =
- try Ast.StringMap.find name env
- with Not_found ->
- failwithf "%a: goal ‘%s’ not found" Ast.string_loc loc name in
- let goal =
- match expr with
- | Ast.EGoal (loc, goal) -> goal
- | _ ->
- failwithf "%a: tried to call ‘%s’ which is not a goal"
- Ast.string_loc loc name in
- run_goal loc env name args goal
-
- (* Look up the variable and substitute it. *)
- | Ast.EVar (loc, name) ->
- let expr =
- try Ast.StringMap.find name env
- with Not_found ->
- failwithf "%a: variable ‘%s’ not found" Ast.string_loc loc name in
- evaluate_target env expr
-
- (* Lists are inlined when found as a target. *)
- | Ast.EList (loc, exprs) ->
- evaluate_targets env exprs
-
- (* A string (with or without substitutions) implies file (filename). *)
- | Ast.ESubsts (loc, str) ->
- let str = substitute loc env str in
- run_goal_for_tactic loc env "file" [Ast.CString str]
-
- | Ast.EConstant (loc, c) ->
- run_goal_for_tactic loc env "file" [c]
-
-(* Find the goal which matches the given tactic and run it.
- * Params is a list of constants.
- *)
-and run_goal_for_tactic loc env tactic const_args =
- (* Search across all goals for a matching tactic. *)
- let goals =
- let env = Ast.StringMap.bindings env in
- filter_map
- (function (name, Ast.EGoal (loc, goal)) -> Some (name, goal) | _ -> None)
- env in
- let name, goal =
- (* If there are multiple goals matching, this must choose
- * the most recently defined (XXX).
- *)
- try
- List.find
- (fun (_, (_, patterns, _, _)) ->
- List.exists (matching_pattern loc env tactic const_args) patterns)
- goals
- with
- Not_found ->
- failwithf "%a: don't know how to build %s %s"
- Ast.string_loc loc
- tactic
- (String.concat ", "
- (List.map (function Ast.CString s -> s) const_args)) in
-
- let args = [] (* XXX calculate free variables *) in
- run_goal loc env name args goal
-
-(* XXX This only does exact matches at the moment. *)
-and matching_pattern loc env tactic const_args = function
- | Ast.PTactic (loc, constructor, params)
- when tactic = constructor &&
- List.length const_args = List.length params ->
- (* Try to simplify the parameters of this pattern down
- * to constants, but don't fail here if we can't do this.
- *)
- (try
- let params = List.map (substitute loc env) params in
- let params = List.map (fun s -> Ast.CString s) params in
- const_args = params
- with Failure _ -> false
- )
+ | ECall (loc, name, args) ->
+ let expr = Ast.getvar env loc name in
+ (match expr with
+ | EGoalDefn _ ->
+ (* Goals don't return anything so they cannot be used in
+ * constant expressions. Use a function instead.
+ *)
+ failwithf "%a: cannot use goal call ‘%s’ in shell expansion"
+ Ast.string_loc loc name
- | Ast.PTactic _ -> false
+ | EFuncDefn (loc, func) ->
+ to_constant env (call_function env loc name args func)
- | Ast.PVar (loc, name) -> assert false
-(*
- NOT IMPLEMENTED - we need variables to contain constructors!
- (try
- let expr = Ast.StringMap.find name env in
- let expr = simplify env expr in
- with Not_found -> false
+ | _ ->
+ failwithf "%a: cannot use ‘%s’ in constant expression"
+ Ast.string_loc loc name
)
-*)
-
-(* Run a named goal. *)
-and run_goal loc env name args (params, patterns, deps, code) =
- (* Substitute the args for the parameters in the environment. *)
- let params =
- try List.combine params args
- with Invalid_argument _ ->
- failwithf "%a: calling goal ‘%s’ with wrong number of arguments"
- Ast.string_loc loc name in
- let env =
- List.fold_left (fun env (k, v) -> Ast.StringMap.add k v env)
- env params in
-
- (* Evaluate the dependencies first. *)
- evaluate_targets env deps;
-
- (* Check if any target needs to be updated. *)
- (* XXX *)
-
- (* Run the code (if any). *)
- (match code with
- | None -> ()
- | Some code ->
- let code = substitute loc env code in
- Printf.printf "running : %s\n" code
- );
-
- (* Check all targets were updated (else it's an error). *)
- (* XXX *)
-
-(* Take any expression and simplify it down to a constant.
- * If the expression cannot be simplified then this throws
- * an error.
- *)
-and simplify env = function
- | Ast.EConstant (loc, c) -> c
- | Ast.EVar (loc, name) ->
- let expr =
- try Ast.StringMap.find name env
- with Not_found ->
- failwithf "%a: variable ‘%s’ not found" Ast.string_loc loc name in
- simplify env expr
-
- | Ast.ESubsts (loc, str) ->
- Ast.CString (substitute loc env str)
+ | ETacticCtor (loc, name, _) ->
+ failwithf "%a: cannot use tactic ‘%s’ in constant expression"
+ Ast.string_loc loc name
- | Ast.EList (loc, _) ->
- failwithf "%a: list found where constant expression expected"
+ | EGoalDefn (loc, _) ->
+ failwithf "%a: cannot use goal in constant expression"
Ast.string_loc loc
- | Ast.ECall (loc, name, _) ->
- failwithf "%a: cannot use goal or tactic ‘%s’ in constant expression"
- Ast.string_loc loc name
+ | EFuncDefn (loc, _) ->
+ failwithf "%a: cannot use function in constant expression"
+ Ast.string_loc loc
- | Ast.EGoal (loc, _) ->
- failwithf "%a: cannot use goal in constant expression"
+ | ETacticDefn (loc, _) ->
+ failwithf "%a: cannot use tactic in constant expression"
Ast.string_loc loc
-(* Take a substitution list and try to turn it into a simple
- * string by evaluating every variable. If not possible this
- * throws an error. Returns a string.
- *)
-and substitute loc env substs =
+and substitute env loc substs =
let b = Buffer.create 13 in
List.iter (
function
| Ast.SString s -> Buffer.add_string b s
- | Ast.SVar name ->
- let expr =
- try Ast.StringMap.find name env
- with Not_found ->
- failwithf "%a: variable ‘%s’ not found" Ast.string_loc loc name in
- match simplify env expr with
+ | SVar name ->
+ let expr = Ast.getvar env loc name in
+ match to_constant env expr with
| Ast.CString s -> Buffer.add_string b s
) substs;
Buffer.contents b
+
+and to_shell_script env loc substs =
+ let b = Buffer.create 13 in
+ List.iter (
+ function
+ | Ast.SString s -> Buffer.add_string b s
+ | SVar name ->
+ let expr = Ast.getvar env loc name in
+ let s = expr_to_shell_string env expr in
+ Buffer.add_string b s
+ ) substs;
+ Buffer.contents b
+
+and expr_to_shell_string env = function
+ | Ast.EConstant (loc, CString s) -> Filename.quote s
+
+ | EVar (loc, name) ->
+ let expr = Ast.getvar env loc name in
+ expr_to_shell_string env expr
+
+ | ESubsts (loc, str) ->
+ Filename.quote (substitute env loc str)
+
+ | EList (loc, exprs) ->
+ let strs = List.map (expr_to_shell_string env) exprs in
+ (* These are shell quoted so we can just concat them with space. *)
+ String.concat " " strs
+
+ | ECall (loc, name, args) ->
+ let expr = Ast.getvar env loc name in
+ (match expr with
+ | EGoalDefn _ ->
+ (* Goals don't return anything so they cannot be used in
+ * shell script expansions. Use a function instead.
+ *)
+ failwithf "%a: cannot use goal call ‘%s’ in shell expansion"
+ Ast.string_loc loc name
+
+ | EFuncDefn (loc, func) ->
+ expr_to_shell_string env (call_function env loc name args func)
+
+ | _ ->
+ failwithf "%a: cannot call ‘%s’ which is not a function"
+ Ast.string_loc loc name
+ )
+
+ (* Tactics expand to the first parameter. *)
+ | ETacticCtor (loc, _, []) -> Filename.quote ""
+ | ETacticCtor (loc, _, (arg :: _)) -> expr_to_shell_string env arg
+
+ | EGoalDefn (loc, _) ->
+ failwithf "%a: cannot use goal in shell expansion"
+ Ast.string_loc loc
+
+ | EFuncDefn (loc, _) ->
+ failwithf "%a: cannot use function in shell expansion"
+ Ast.string_loc loc
+
+ | ETacticDefn (loc, _) ->
+ failwithf "%a: cannot use tactic in shell expansion"
+ Ast.string_loc loc
+
+and run_code ?(quiet = false) env loc code =
+ let code = to_shell_script env loc code in
+ let code =
+ "source " ^ Filename.quote Cmdline.prelude_sh_file ^ "\n" ^
+ "set -e\n" ^
+ (if not quiet then "set -x\n" else "") ^
+ "\n" ^
+ code in
+
+ let chan = Unix.open_process_in code in
+ let b = Buffer.create 1024 in
+ (try
+ while true do
+ Buffer.add_string b (input_line chan);
+ Buffer.add_char b '\n'
+ done
+ with End_of_file -> ());
+ let st = Unix.close_process_in chan in
+ let i =
+ match st with
+ | Unix.WEXITED i -> i
+ | Unix.WSIGNALED i ->
+ failwithf "%a: killed by signal %d" Ast.string_loc loc i
+ | Unix.WSTOPPED i ->
+ failwithf "%a: stopped by signal %d" Ast.string_loc loc i in
+ i, Buffer.contents b
+
+and evaluate_goal_arg env = function
+ | Ast.EVar (loc, name) ->
+ let expr = Ast.getvar env loc name in
+ evaluate_goal_arg env expr
+
+ | ESubsts (loc, str) ->
+ let str = substitute env loc str in
+ Ast.EConstant (loc, Ast.CString str)
+
+ | EList (loc, exprs) ->
+ Ast.EList (loc, List.map (evaluate_goal_arg env) exprs)
+
+ | ETacticCtor (loc, name, exprs) ->
+ Ast.ETacticCtor (loc, name, List.map (evaluate_goal_arg env) exprs)
+
+ | ECall (loc, name, args) ->
+ let expr = Ast.getvar env loc name in
+ (match expr with
+ | EGoalDefn _ ->
+ (* Goals don't return anything so they cannot be used in
+ * goal args. Use a function instead.
+ *)
+ failwithf "%a: cannot use goal call ‘%s’ in goal argument"
+ Ast.string_loc loc name
+
+ | EFuncDefn (loc, func) ->
+ call_function env loc name args func
+
+ | _ ->
+ failwithf "%a: cannot call ‘%s’ which is not a function"
+ Ast.string_loc loc name
+ )
+
+ | EConstant _
+ | EGoalDefn _
+ | EFuncDefn _
+ | ETacticDefn _ as e -> e
+
+(* Functions are only called from goal args or when substituting
+ * into a shell script or constant expression (this may change if we
+ * implement ‘:=’ assignment for variables). This evaluates a
+ * function by running the associated shell script and parsing
+ * the output as an expression, string or list of strings.
+ *)
+and call_function env loc name args (params, returning, code) =
+ (* This is used to print the function in debug and error messages only. *)
+ let debug_func =
+ sprintf "%s (%s) returning %s" name
+ (String.concat ", " (List.map (Ast.string_expr ()) args))
+ (match returning with RetExpr -> "expression"
+ | RetString -> "string"
+ | RetStrings -> "strings") in
+ Cmdline.debug "%a: running function %s" Ast.string_loc loc debug_func;
+
+ (* Evaluate function args. Must be done before updating the environment. *)
+ let args = List.map (evaluate_goal_arg env) args in
+
+ (* Create a new environment which maps the parameter names to
+ * the args.
+ *)
+ let env =
+ let params =
+ try List.combine params args
+ with Invalid_argument _ ->
+ failwithf "%a: calling function %s with wrong number of arguments, expecting %d args but got %d args"
+ Ast.string_loc loc debug_func
+ (List.length params) (List.length args) in
+ List.fold_left (fun env (k, v) -> Ast.Env.add k v env) env params in
+
+ let r, b = run_code env loc code in
+ if r <> 0 then (
+ eprintf "*** function ‘%s’ failed with exit code %d\n" name r;
+ exit 1
+ );
+
+ match returning with
+ | RetExpr -> Parse.parse_expr (sprintf "function:%s" name) b
+ | RetString -> Ast.EConstant (loc, Ast.CString b)
+ | RetStrings ->
+ (* run_code always adds \n after the final line, so when we
+ * read it back we will get a final empty string which we
+ * have to drop. XXX Probably better to preserve the lines
+ * read from the external command.
+ *)
+ let strs = nsplit "\n" b in
+ let strs = List.rev strs in
+ let strs = match strs with "" :: xs -> xs | xs -> xs in
+ let strs = List.rev strs in
+ let strs = List.map (fun s -> Ast.EConstant (loc, Ast.CString s)) strs in
+ EList (loc, strs)