1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
|
@z --- val.hweb ---
FWEB version 1.62 (September 25, 1998)
Based on version 0.5 of S. Levy's CWEB [copyright (C) 1987 Princeton University]
@x-----------------------------------------------------------------------------
@ Here are declarations needed for \.{eval.web}.
@<Typedef declarations@>=
/* Precedence of the various operators. */
typedef enum {BAD_TOKEN,OR_OR,AND_AND,BIT_OR,BIT_XOR,BIT_AND,LOG_EQ,LOG_LT,
BIT_SHIFT,PLUS_MINUS,TIMES,EXP,UNARY,HIGHEST_UNARY} @]PRECEDENCE;
/* An operator, together with its precedence. */
typedef struct
{
eight_bits token;
PRECEDENCE precedence;
} @]OP;
/* The actual data value. */
typedef union
{
long i; // All integers are long, to humor the pc people.
double d; // We handle just one floating-point type.
sixteen_bits id; // An identifier token.
OP op;
} @]VALUE;
/* Type of the data value. The relative order must be preserved here,
because it is used in the type promotion routine |promote|. */
typedef enum {Int,Double,Id,Op} @]TYPE;
/* Complete data structure for the token; includes links to the next and
last |VAL| structures. */
typedef struct val
{
VALUE value; // The actual data value or operator token.
TYPE type; // The type of value stored in |value|.
struct val HUGE *last, HUGE *next;// Link to the last and next values.
} @]VAL;
|
