| 24 |
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| 25 |
/* First, define some types. */ |
/* First, define some types. */ |
| 26 |
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| 27 |
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struct cons_struct; |
| 28 |
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struct symbol_struct; |
| 29 |
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| 30 |
/* A value of some type */ |
/* A value of some type */ |
| 31 |
typedef struct { |
typedef struct { |
| 32 |
enum { |
enum { |
| 34 |
tfloat, |
tfloat, |
| 35 |
string, |
string, |
| 36 |
func, /* Function pointer */ |
func, /* Function pointer */ |
| 37 |
symb, |
symb, /* Symbol */ |
| 38 |
list |
tcons /* A pair of two values */ |
| 39 |
} type:4; /* Type of stack element */ |
} type:4; /* Type of stack element */ |
| 40 |
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| 41 |
union { |
union { |
| 42 |
struct { |
struct { |
| 43 |
unsigned int mark:1; |
unsigned int mark:1; /* Used internally in the GC */ |
| 44 |
unsigned int protect:1; |
unsigned int protect:1; /* Protect from GC */ |
| 45 |
} flag; |
} flag; |
| 46 |
unsigned int no_gc:2; |
unsigned int no_gc:2; /* Both flags as one integer */ |
| 47 |
} gc; |
} gc; /* Garbage collector stuff */ |
| 48 |
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| 49 |
union { |
union { |
| 50 |
void *ptr; /* Pointer to the content */ |
void *ptr; /* Pointer to the content */ |
| 51 |
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struct cons_struct *c; /* ...or a pointer to a cons cell */ |
| 52 |
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struct symbol_struct *sym; /* ...or a pointer to a symbol */ |
| 53 |
int i; /* ...or an integer */ |
int i; /* ...or an integer */ |
| 54 |
float f; |
float f; /* ...or a floating point number */ |
| 55 |
} content; /* Stores a pointer or an integer */ |
} content; /* Stores a pointer or an integer */ |
| 56 |
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| 57 |
} value; |
} value; |
| 58 |
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| 59 |
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/* An item (value) on a stack */ |
| 60 |
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typedef struct stackitem_struct |
| 61 |
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{ |
| 62 |
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value *item; /* The value on the stack */ |
| 63 |
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/* (This is never NULL) */ |
| 64 |
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struct stackitem_struct *next; /* Next item */ |
| 65 |
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} stackitem; |
| 66 |
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| 67 |
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typedef struct cons_struct { /* A pair of two values */ |
| 68 |
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value *car; |
| 69 |
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value *cdr; |
| 70 |
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} cons; |
| 71 |
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| 72 |
/* A symbol with a name and possible value */ |
/* A symbol with a name and possible value */ |
| 73 |
/* (These do not need reference counters, they are kept unique by |
/* (These do not need reference counters, they are kept unique by |
| 74 |
hashing.) */ |
hashing.) */ |
| 81 |
/* A type for a hash table for symbols */ |
/* A type for a hash table for symbols */ |
| 82 |
typedef symbol *hashtbl[HASHTBLSIZE]; /* Hash table declaration */ |
typedef symbol *hashtbl[HASHTBLSIZE]; /* Hash table declaration */ |
| 83 |
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/* An item (value) on a stack */ |
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typedef struct stackitem_struct |
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{ |
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value *item; /* The value on the stack */ |
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/* (This is never NULL) */ |
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struct stackitem_struct *next; /* Next item */ |
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} stackitem; |
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| 84 |
/* An environment; gives access to the stack and a hash table of |
/* An environment; gives access to the stack and a hash table of |
| 85 |
defined symbols */ |
defined symbols */ |
| 86 |
typedef struct { |
typedef struct { |
| 87 |
stackitem *gc_ref; |
stackitem *gc_ref; |
| 88 |
int gc_limit, gc_count; |
int gc_limit, gc_count; |
| 89 |
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| 90 |
stackitem *head; /* Head of the stack */ |
value *head; /* Head of the stack */ |
| 91 |
hashtbl symbols; /* Hash table of all variable bindings */ |
hashtbl symbols; /* Hash table of all variable bindings */ |
| 92 |
int err; /* Error flag */ |
int err; /* Error flag */ |
| 93 |
char *in_string; /* Input pending to be read */ |
char *in_string; /* Input pending to be read */ |
| 118 |
void push_sym(environment*, const char*); |
void push_sym(environment*, const char*); |
| 119 |
extern void nl(); |
extern void nl(); |
| 120 |
extern void type(environment*); |
extern void type(environment*); |
| 121 |
void print_h(stackitem*, int); |
void print_h(value*, int); |
| 122 |
extern void print_(environment*); |
extern void print_(environment*); |
| 123 |
extern void print(environment*); |
extern void print(environment*); |
| 124 |
extern void princ_(environment*); |
extern void princ_(environment*); |
| 125 |
extern void princ(environment*); |
extern void princ(environment*); |
| 126 |
void print_st(stackitem*, long); |
void print_st(value*, long); |
| 127 |
extern void printstack(environment*); |
extern void printstack(environment*); |
| 128 |
extern void swap(environment*); |
extern void swap(environment*); |
| 129 |
extern void rot(environment*); |
extern void rot(environment*); |