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Lexical scoping is working, but `defun` broke because of that.

Need macros next
master
FelixBrendel 7 лет назад
Родитель
Сommit
9b5692da9d
7 измененных файлов: 325 добавлений и 290 удалений
  1. +192
    -191
      bin/pre.slime
  2. +23
    -6
      bin/test.slime
  3. +3
    -2
      src/ast.cpp
  4. +41
    -4
      src/built_ins.cpp
  5. +62
    -82
      src/env.cpp
  6. +2
    -3
      src/eval.cpp
  7. +2
    -2
      src/main.cpp

+ 192
- 191
bin/pre.slime Просмотреть файл

@@ -1,196 +1,197 @@
(define defmacro
(macro (@name @params :rest @body)
"Macro for creating macros with a more concise syntax."
(eval (pair 'define (pair @name (pair (pair 'macro (pair @params @body)) nil))))))
(eval (pair 'define-upwards (pair @name (pair (pair 'macro (pair @params @body)) nil))))))

(defmacro defun (@name @params :rest @body)
(define defun
(macro (@name @params :rest @body)
"Macro for creating functions with a more concise syntax."
(eval (pair 'define (pair @name (pair (pair 'lambda (pair @params @body)) nil)))))
(defun nil? (x)
"Checks if the argument is nil."
(= x nil))
(defun number? (x)
"Checks if the argument is a number."
(= (type x) :number))
(defun symbol? (x)
"Checks if the argument is a symbol."
(= (type x) :symbol))
(defun keyword? (x)
"Checks if the argument is a keyword."
(= (type x) :keyword))
(defun pair? (x)
"Checks if the argument is a pair."
(= (type x) :pair))
(defun string? (x)
"Checks if the argument is a string."
(= (type x) :string))
(defun dynamic-function? (x)
"Checks if the argument is a function."
(= (type x) :dynamic-function))
(defun dynamic-macro? (x)
"Checks if the argument is a macro."
(= (type x) :dynamic-macro))
(defun built-in-function? (x)
"Checks if the argument is a built-in function."
(= (type x) :built-in-function))
(defun apply (fun seq)
"Applies the funciton to the sequence, as in calls the funciton with
ithe sequence as arguemens."
(eval (pair fun seq)))
(defmacro when (@test :rest @body)
"Executes the code in :rest if test is true."
(if (eval @test)
(eval (pair prog @body))
nil))
(defmacro unless (@test :rest @body)
"Executes the code in :rest if test is false."
(if (eval @test)
nil
(eval (pair prog @body))))
(defun end (seq)
"Returns the last pair in the sqeuence."
(if (or (nil? seq) (not (pair? (rest seq))))
seq
(end (rest seq))))
(defun last (seq)
"Returns the (first) of the last (pair) of the given sequence."
(first (end seq)))
(defun extend (seq elem)
"Extends a list with the given element, by putting it in
the (rest) of the last element of the sequence."
(when (pair? seq)
(define e (end seq))
(mutate e (pair (first e) elem)))
seq)
(defun incr (val)
"Adds one to the argument."
(+ val 1))
(defun decr (val)
"Subtracts one from the argument."
(- val 1))
(defun append (seq elem)
"Appends an element to a sequence, by extendeing the list
with (pair elem nil)."
(extend seq (pair elem nil)))
(defun length (seq)
"Returns the length of the given sequence."
(if (nil? seq)
0
(incr (length (rest seq)))))
(defmacro n-times (@times @action)
"Executes @action @times times."
(unless (<= (eval @times) 0)
(eval @action)
(apply n-times (list (list - @times 1) @action))))
(defmacro for (@symbol @from @to :rest @for-body)
"Designed to resemble a C style for loop. It takes a symbol as
well as its starting number and end number and executes the
@for-body with the defined symbol for all numbers between @from
to @to, where @to is exclusive."
(if (< (eval @from) (eval @to))
(macro-define @op incr)
(if (> (eval @from) (eval @to))
(macro-define @op decr)
(macro-define @op nil)))
(when @op
(macro-define (eval @symbol) (eval @from))
(eval (pair prog @for-body))
(eval (extend (list for @symbol (@op @from) @to) @for-body))))
(defun range (:keys from :defaults-to 0 to)
"Returns a sequence of numbers starting with the number defined
by the key 'from' and ends with the number defined in 'to'."
(when (< from to)
(pair from (range :from (+ 1 from) :to to))))
(defun range-while (:keys from :defaults-to 0 to)
"Returns a sequence of numbers starting with the number defined
by the key 'from' and ends with the number defined in 'to'."
(define result (list (copy from)))
(define head result)
(mutate from (incr from))
(while (< from to)
(prog
(mutate head (pair (first head) (pair (copy from) nil)))
(define head (rest head))
(mutate from (incr from))))
result)
(defun map (fun seq)
"Takes a function and a sequence as arguments and returns a new
sequence which contains the results of using the first sequences
elemens as argument to that function."
(if (nil? seq)
seq
(pair (fun (first seq))
(map fun (rest seq)))))
(defun reduce (fun seq)
"Takes a function and a sequence as arguments and applies the
function to the argument sequence. This only works correctly if
the given function accepts a variable amount of parameters. If
your funciton is limited to two arguments, use `reduce-binary'
instead."
(apply fun seq))
(defun reduce-binary (fun seq)
"Takes a function and a sequence as arguments and applies the
function to the argument sequence. reduce-binary applies the
arguments `pair-wise' which means it works with binary functions
as compared to `reduce'."
(if (nil? (rest seq))
(first seq)
(fun (first seq)
(reduce-binary fun (rest seq)))))
(defun filter (fun seq)
"Takes a function and a sequence as arguments and applies the
function to every value in the sequence. If the result of that
funciton application returns a truthy value, the original value is
added to a list, which in the end is returned."
(when seq
(if (fun (first seq))
(pair (first seq)
(filter fun (rest seq)))
(filter fun (rest seq)))))
(defun printf (:keys sep :defaults-to " " end :defaults-to "\n" :rest args)
"A wrapper for the built-in (print) that accepts a variable number
of arguments and also provides keywords for specifying the printed
separators between the arguments and what should be printed after the
las argument."
(defmacro printf-quoted (:keys @sep @end :rest @args)
(if (nil? @args)
(prog (print (eval @end)) nil)
(prog
(print (first @args))
(unless (nil? (rest @args))
(print (eval @sep)))
(eval (pair printf-quoted
(extend (list :@sep (eval @sep) :@end (eval @end)) (rest @args)))))))
(eval (pair printf-quoted (extend (list :@sep (eval sep) :@end (eval end)) args))))
(defmacro pe (@expr)
(printf @expr "evaluates to" (eval @expr)))
(eval (pair 'define-upwards (pair @name (pair (pair 'lambda (pair @params @body)) nil))))))
;; (defun nil? (x)
;; "Checks if the argument is nil."
;; (= x nil))
;; (defun number? (x)
;; "Checks if the argument is a number."
;; (= (type x) :number))
;; (defun symbol? (x)
;; "Checks if the argument is a symbol."
;; (= (type x) :symbol))
;; (defun keyword? (x)
;; "Checks if the argument is a keyword."
;; (= (type x) :keyword))
;; (defun pair? (x)
;; "Checks if the argument is a pair."
;; (= (type x) :pair))
;; (defun string? (x)
;; "Checks if the argument is a string."
;; (= (type x) :string))
;; (defun dynamic-function? (x)
;; "Checks if the argument is a function."
;; (= (type x) :dynamic-function))
;; (defun dynamic-macro? (x)
;; "Checks if the argument is a macro."
;; (= (type x) :dynamic-macro))
;; (defun built-in-function? (x)
;; "Checks if the argument is a built-in function."
;; (= (type x) :built-in-function))
;; (defun apply (fun seq)
;; "Applies the funciton to the sequence, as in calls the function
;; with ithe sequence as arguemens."
;; (eval (pair fun seq)))
;; (defmacro when (@test :rest @body)
;; "Executes the code in :rest if test is true."
;; (if (eval @test)
;; (eval (pair prog @body))
;; nil))
;; (defmacro unless (@test :rest @body)
;; "Executes the code in :rest if test is false."
;; (if (eval @test)
;; nil
;; (eval (pair prog @body))))
;; (defun end (seq)
;; "Returns the last pair in the sqeuence."
;; (if (or (nil? seq) (not (pair? (rest seq))))
;; seq
;; (end (rest seq))))
;; (defun last (seq)
;; "Returns the (first) of the last (pair) of the given sequence."
;; (first (end seq)))
;; (defun extend (seq elem)
;; "Extends a list with the given element, by putting it in
;; the (rest) of the last element of the sequence."
;; (when (pair? seq)
;; (define e (end seq))
;; (mutate e (pair (first e) elem)))
;; seq)
;; (defun incr (val)
;; "Adds one to the argument."
;; (+ val 1))
;; (defun decr (val)
;; "Subtracts one from the argument."
;; (- val 1))
;; (defun append (seq elem)
;; "Appends an element to a sequence, by extendeing the list
;; with (pair elem nil)."
;; (extend seq (pair elem nil)))
;; (defun length (seq)
;; "Returns the length of the given sequence."
;; (if (nil? seq)
;; 0
;; (incr (length (rest seq)))))
;; (defmacro n-times (@times @action)
;; "Executes @action @times times."
;; (unless (<= (eval @times) 0)
;; (eval @action)
;; (apply n-times (list (list - @times 1) @action))))
;; (defmacro for (@symbol @from @to :rest @for-body)
;; "Designed to resemble a C style for loop. It takes a symbol as
;; well as its starting number and end number and executes the
;; @for-body with the defined symbol for all numbers between @from
;; to @to, where @to is exclusive."
;; (if (< (eval @from) (eval @to))
;; (macro-define @op incr)
;; (if (> (eval @from) (eval @to))
;; (macro-define @op decr)
;; (macro-define @op nil)))
;; (when @op
;; (macro-define (eval @symbol) (eval @from))
;; (eval (pair prog @for-body))
;; (eval (extend (list for @symbol (@op @from) @to) @for-body))))
;; (defun range (:keys from :defaults-to 0 to)
;; "Returns a sequence of numbers starting with the number defined
;; by the key 'from' and ends with the number defined in 'to'."
;; (when (< from to)
;; (pair from (range :from (+ 1 from) :to to))))
;; (defun range-while (:keys from :defaults-to 0 to)
;; "Returns a sequence of numbers starting with the number defined
;; by the key 'from' and ends with the number defined in 'to'."
;; (define result (list (copy from)))
;; (define head result)
;; (mutate from (incr from))
;; (while (< from to)
;; (prog
;; (mutate head (pair (first head) (pair (copy from) nil)))
;; (define head (rest head))
;; (mutate from (incr from))))
;; result)
;; (defun map (fun seq)
;; "Takes a function and a sequence as arguments and returns a new
;; sequence which contains the results of using the first sequences
;; elemens as argument to that function."
;; (if (nil? seq)
;; seq
;; (pair (fun (first seq))
;; (map fun (rest seq)))))
;; (defun reduce (fun seq)
;; "Takes a function and a sequence as arguments and applies the
;; function to the argument sequence. This only works correctly if
;; the given function accepts a variable amount of parameters. If
;; your funciton is limited to two arguments, use `reduce-binary'
;; instead."
;; (apply fun seq))
;; (defun reduce-binary (fun seq)
;; "Takes a function and a sequence as arguments and applies the
;; function to the argument sequence. reduce-binary applies the
;; arguments `pair-wise' which means it works with binary functions
;; as compared to `reduce'."
;; (if (nil? (rest seq))
;; (first seq)
;; (fun (first seq)
;; (reduce-binary fun (rest seq)))))
;; (defun filter (fun seq)
;; "Takes a function and a sequence as arguments and applies the
;; function to every value in the sequence. If the result of that
;; funciton application returns a truthy value, the original value is
;; added to a list, which in the end is returned."
;; (when seq
;; (if (fun (first seq))
;; (pair (first seq)
;; (filter fun (rest seq)))
;; (filter fun (rest seq)))))
;; (defun printf (:keys sep :defaults-to " " end :defaults-to "\n" :rest args)
;; "A wrapper for the built-in (print) that accepts a variable number
;; of arguments and also provides keywords for specifying the printed
;; separators between the arguments and what should be printed after the
;; las argument."
;; (defmacro printf-quoted (:keys @sep @end :rest @args)
;; (if (nil? @args)
;; (prog (print (eval @end)) nil)
;; (prog
;; (print (first @args))
;; (unless (nil? (rest @args))
;; (print (eval @sep)))
;; (eval (pair printf-quoted
;; (extend (list :@sep (eval @sep) :@end (eval @end)) (rest @args)))))))
;; (eval (pair printf-quoted (extend (list :@sep (eval sep) :@end (eval end)) args))))
;; (defmacro pe (@expr)
;; (printf @expr "evaluates to" (eval @expr)))

+ 23
- 6
bin/test.slime Просмотреть файл

@@ -1,12 +1,29 @@

(defun make-vector (x y z)
(let ((local-x x)
(local-y y)
(local-z z))
(lambda ()
local-x)))
(let ((local-x x)
(local-y y)
(local-z z)
(defun (macro (@name @params :rest @body)
(eval (pair 'define-upwards (pair @name (pair (pair 'lambda (pair @params @body)) nil)))))))

(defun set-x (new-x) (mutate local-x new-x))
(defun set-y (new-y) (mutate local-y new-y))
(defun set-z (new-z) (mutate local-z new-z))

(defun dispatch (message)
(if (= message ::get-x)
local-x
(if (= message ::set-x)
set-x
nil)))

(break)
dispatch))

(define v (make-vector 1 2 3))
(print (v))

(print (v ::get-x))
((v ::set-x) 19)
(print (v ::get-x))

(read " ")

+ 3
- 2
src/ast.cpp Просмотреть файл

@@ -109,6 +109,7 @@ void append_to_keyword_argument_list(Keyword_Arguments* args,
append_to_Ast_Node_array_list(args->values, default_value);
}

struct Environment;

struct Function {
bool is_macro;
@@ -117,10 +118,10 @@ struct Function {
Keyword_Arguments* keyword_arguments;
// rest_argument will be nullptr if no rest argument is declared
char* rest_argument;
struct Ast_Node* body; // implicit prog
Ast_Node* body; // implicit prog
Environment* parent_environment; // we are doing closures now!!
};

struct Environment;

struct CFunction {
std::function<Ast_Node*(Ast_Node*, Environment*)> function;


+ 41
- 4
src/built_ins.cpp Просмотреть файл

@@ -324,7 +324,7 @@ void load_built_ins_into_environment(Environment* env) {

return value;
});
defun("macro-define", cLambda {
defun("define-upwards", cLambda {
try {
arguments_length = list_length(arguments);
}
@@ -345,15 +345,50 @@ void load_built_ins_into_environment(Environment* env) {
report_error(Error_Type::Type_Missmatch);
}

if (!env->parent) {
report_error(Error_Type::Unknown_Error);
}


Ast_Node* value = arguments->value.pair->rest->value.pair->first;
try {
value = eval_expr(value, env);
}

define_macro_symbol(symbol, value, env);
define_symbol(symbol, value, env->parent);

return value;
});
// defun("macro-define", cLambda {
// try {
// arguments_length = list_length(arguments);
// }

// if (arguments_length != 2) {
// report_error(Error_Type::Wrong_Number_Of_Arguments);
// }

// Ast_Node* symbol = arguments->value.pair->first;

// if (symbol->type == Ast_Node_Type::Pair) {
// try {
// symbol = eval_expr(symbol, env);
// }
// }

// if (symbol->type != Ast_Node_Type::Symbol) {
// report_error(Error_Type::Type_Missmatch);
// }

// Ast_Node* value = arguments->value.pair->rest->value.pair->first;
// try {
// value = eval_expr(value, env);
// }

// define_macro_symbol(symbol, value, env);

// return value;
// });
defun("mutate", cLambda {
try {
evaluated_arguments = eval_arguments(arguments, env, &arguments_length);
@@ -500,7 +535,7 @@ void load_built_ins_into_environment(Environment* env) {
if (arguments_length < 1)
report_error(Error_Type::Wrong_Number_Of_Arguments);

Environment* let_env = create_child_environment(env, Environment_Type::Let);
Environment* let_env = create_child_environment(env);
Ast_Node* bindings = arguments->value.pair->first;
while (true) {
if (bindings->type == Ast_Node_Type::Nil) {
@@ -564,6 +599,7 @@ void load_built_ins_into_environment(Environment* env) {
/* if (lispOperator->value.built_in_function->type == Built_In_Macro) { */
/* function->is_macro = true; */
/* } else { */
function->parent_environment = env;
function->is_macro = false;
/* } */

@@ -614,6 +650,7 @@ void load_built_ins_into_environment(Environment* env) {
report_error(Error_Type::Wrong_Number_Of_Arguments);

Function* function = new(Function);
function->parent_environment = env;
function->is_macro = true;

// if parameters were specified
@@ -962,7 +999,7 @@ void load_built_ins_into_environment(Environment* env) {
}

Environment* create_built_ins_environment() {
Environment* ret = create_child_environment(nullptr, Environment_Type::Let);
Environment* ret = create_child_environment(nullptr);
load_built_ins_into_environment(ret);
return ret;
}

+ 62
- 82
src/env.cpp Просмотреть файл

@@ -1,12 +1,5 @@
enum struct Environment_Type {
Let,
Lambda,
Macro,
};

struct Environment {
struct Environment* parent;
Environment_Type type;

int capacity;
int next_index;
@@ -15,12 +8,11 @@ struct Environment {
Ast_Node** values;
};

Environment* create_child_environment(Environment* parent, Environment_Type type) {
Environment* create_child_environment(Environment* parent) {
Environment* env = new(Environment);

int start_capacity = 16;

env->type = type;
env->parent = parent;
env->capacity = start_capacity;
env->next_index = 0;
@@ -30,19 +22,19 @@ Environment* create_child_environment(Environment* parent, Environment_Type type
return env;
}

Environment* create_empty_environment(Environment_Type type) {
return create_child_environment(nullptr, type);
Environment* create_empty_environment() {
return create_child_environment(nullptr);
}

void define_symbol(Ast_Node* symbol, Ast_Node* value, Environment* env) {
if (env->type == Environment_Type::Macro) {
// NOTE(Felix): we know we have a parent because every
// environment has a parent except the top level environment.
// However the top level environment is not a let-environment,
// so we would not land here
define_symbol(symbol, value, env->parent);
return;
}
// if (env->type == Environment_Type::Macro) {
// // NOTE(Felix): we know we have a parent because every
// // environment has a parent except the top level environment.
// // However the top level environment is not a let-environment,
// // so we would not land here
// define_symbol(symbol, value, env->parent);
// return;
// }

// NOTE(Felix): right now we are simply adding the symol at the
// back of the list without checking if it already exists but are
@@ -60,16 +52,16 @@ void define_symbol(Ast_Node* symbol, Ast_Node* value, Environment* env) {
++env->next_index;
}

void define_macro_symbol(Ast_Node* symbol, Ast_Node* value, Environment* env) {
if (env->type != Environment_Type::Macro) {
create_error(Error_Type::Unknown_Error, symbol->sourceCodeLocation);
return;
}
// void define_macro_symbol(Ast_Node* symbol, Ast_Node* value, Environment* env) {
// if (env->type != Environment_Type::Macro) {
// create_error(Error_Type::Unknown_Error, symbol->sourceCodeLocation);
// return;
// }

env->type = Environment_Type::Lambda;
define_symbol(symbol, value, env);
env->type = Environment_Type::Macro;
}
// env->type = Environment_Type::Lambda;
// define_symbol(symbol, value, env);
// env->type = Environment_Type::Macro;
// }

void print_environment(Environment* env);

@@ -80,41 +72,41 @@ Ast_Node* lookup_symbol_in_this_envt(Symbol* sym, Environment* env) {
return nullptr;
}

Ast_Node* lookup_symbol_from_lambda_env(Symbol* sym, Environment* env) {
Ast_Node* result;
do {
if (env->type != Environment_Type::Lambda) {
result = lookup_symbol_in_this_envt(sym, env);
if (result) return result;
}
env = env->parent;
} while (env);
return nullptr;
}
Ast_Node* lookup_symbol_from_let_or_macro_env(Symbol* sym, Environment* env) {
Ast_Node* result;
do {
result = lookup_symbol_in_this_envt(sym, env);
if (result) return result;
if (env->type == Environment_Type::Lambda)
break;
env = env->parent;
} while (env);
if (env) {
do {
if (env->type != Environment_Type::Lambda) {
result = lookup_symbol_in_this_envt(sym, env);
if (result) return result;
}
env = env->parent;
} while (env);
}
return nullptr;
}
// Ast_Node* lookup_symbol_from_lambda_env(Symbol* sym, Environment* env) {
// Ast_Node* result;
// do {
// if (env->type != Environment_Type::Lambda) {
// result = lookup_symbol_in_this_envt(sym, env);
// if (result) return result;
// }
// env = env->parent;
// } while (env);
// return nullptr;
// }
// Ast_Node* lookup_symbol_from_let_or_macro_env(Symbol* sym, Environment* env) {
// Ast_Node* result;
// do {
// result = lookup_symbol_in_this_envt(sym, env);
// if (result) return result;
// if (env->type == Environment_Type::Lambda)
// break;
// env = env->parent;
// } while (env);
// if (env) {
// do {
// if (env->type != Environment_Type::Lambda) {
// result = lookup_symbol_in_this_envt(sym, env);
// if (result) return result;
// }
// env = env->parent;
// } while (env);
// }
// return nullptr;
// }

Ast_Node* lookup_symbol(Ast_Node* node, Environment* env) {
// first check current environment
@@ -125,11 +117,7 @@ Ast_Node* lookup_symbol(Ast_Node* node, Environment* env) {
return result;

if (env->parent) {
if (env->type == Environment_Type::Lambda) {
result = lookup_symbol_from_lambda_env(sym, env->parent);
} else {
result = lookup_symbol_from_let_or_macro_env(sym, env->parent);
}
result = lookup_symbol(node, env->parent);

if (result)
return result;
@@ -142,14 +130,6 @@ Ast_Node* lookup_symbol(Ast_Node* node, Environment* env) {
return create_ast_node_t();
}

// we should not need this anymore when we have c lambdas as built
// in functions

/* result = create_ast_node_built_in_function(sym->identifier); */
/* result->sourceCodeLocation = node->sourceCodeLocation; */
/* if (result) */
/* return result; */

create_error(Error_Type::Symbol_Not_Defined, node->sourceCodeLocation);
/* printf("%s\n", sym->identifier); */
return nullptr;
@@ -170,12 +150,12 @@ void print_environment_indent(Environment* env, int indent) {
if (env->parent) {
print_indent(indent);
printf("parent");
if (env->parent->type == Environment_Type::Lambda)
printf(" (lambda)");
else if (env->parent->type == Environment_Type::Macro)
printf(" (macro)");
else if (env->parent->type == Environment_Type::Let)
printf(" (let)");
// if (env->parent->type == Environment_Type::Lambda)
// printf(" (lambda)");
// else if (env->parent->type == Environment_Type::Macro)
// printf(" (macro)");
// else if (env->parent->type == Environment_Type::Let)
// printf(" (let)");
printf(":\n");
print_environment_indent(env->parent, indent+4);
}


+ 2
- 3
src/eval.cpp Просмотреть файл

@@ -6,7 +6,8 @@ Ast_Node* apply_arguments_to_function(Ast_Node* arguments, Function* function, E
// switching between "define_symbol" and "define_macro_symbol" all
// the time

Environment* new_env = create_child_environment(parent, Environment_Type::Lambda);
// Environment* new_env = create_child_environment(parent, Environment_Type::Lambda);
Environment* new_env = create_child_environment(function->parent_environment);

// positional arguments
for (int i = 0; i < function->positional_arguments->next_index; ++i) {
@@ -145,8 +146,6 @@ Ast_Node* apply_arguments_to_function(Ast_Node* arguments, Function* function, E

// don't have to check every time if it is macro environment or
// not
if (function->is_macro)
new_env->type = Environment_Type::Macro;

try {
result = eval_expr(function->body, new_env);


+ 2
- 2
src/main.cpp Просмотреть файл

@@ -30,7 +30,7 @@ Ast_Node* interprete_file (char* file_name) {
program = parse_program(file_name, file_content);
}

Environment* env = create_empty_environment(Environment_Type::Let);
Environment* env = create_empty_environment();
load_built_ins_into_environment(env);

try {
@@ -50,7 +50,7 @@ Ast_Node* interprete_file (char* file_name) {
int interprete_stdin () {
printf("Welcome to the lispy interpreter.\n");
char* line;
Environment* env = create_empty_environment(Environment_Type::Let);
Environment* env = create_empty_environment();
load_built_ins_into_environment(env);

built_in_load("pre.slime", env);


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