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include <lexnum.h>
include <ctype.h>
include <mach.h>
include <math.h>
include <evvexpr.h>
# Parser definitions.
define CONSTANT 257
define IDENTIFIER 258
define NEWLINE 259
define YYEOS 260
define PLUS 261
define MINUS 262
define STAR 263
define SLASH 264
define EXPON 265
define CONCAT 266
define QUEST 267
define COLON 268
define LT 269
define GT 270
define LE 271
define EQ 272
define NE 273
define SE 274
define LAND 275
define LOR 276
define LNOT 277
define BAND 278
define BOR 279
define BXOR 280
define BNOT 281
define AT 282
define GE 283
define UMINUS 284
# XVV_GETTOK -- Lexical analyzer for EVVEXPR. Returns the token code as the
# function value. If the token is an operand (identifier or constant) the
# operand value is returned in OUT.
int procedure xvv_gettok (ip, out)
pointer ip #I pointer into input string (expression)
pointer out #I pointer to yacc YYLVAL token value operand
char ch
long lval
double dval
pointer ip_start
char numbuf[MAX_DIGITS]
int nchars, token, junk, dtype
int stridx(), stridxs(), lexnum(), gctod(), gctol()
define ident_ 91
begin
while (IS_WHITE(Memc[ip]))
ip = ip + 1
ch = Memc[ip]
switch (ch) {
case 'A', 'B', 'C', 'D', 'E', 'F', 'G', 'H', 'J', 'K', 'L', 'M',
'N', 'O', 'P', 'Q', 'R', 'S', 'T', 'U', 'V', 'W', 'X', 'Y', 'Z',
'a', 'b', 'c', 'd', 'e', 'f', 'g', 'h', 'i', 'j', 'k', 'l', 'm',
'n', 'o', 'p', 'q', 'r', 's', 't', 'u', 'v', 'w', 'x', 'y', 'z':
# Return an identifier.
ident_
ip_start = ip
while (IS_ALNUM(ch) || stridx (ch, "_.$@#%&;[]\\^{}~") > 0) {
ip = ip + 1
ch = Memc[ip]
}
nchars = ip - ip_start
call xvv_initop (out, nchars, TY_CHAR)
call strcpy (Memc[ip_start], O_VALC(out), nchars)
return (IDENTIFIER)
case 'I', '.', '0', '1', '2', '3', '4', '5', '6', '7', '8', '9':
# Return a numeric constant. The character I vectors here so
# that we can check for INDEF, a legal number.
token = lexnum (Memc, ip, nchars)
switch (token) {
case LEX_OCTAL:
junk = gctol (Memc, ip, lval, 8)
call xvv_initop (out, 0, TY_INT)
O_VALI(out) = lval
case LEX_DECIMAL:
junk = gctol (Memc, ip, lval, 10)
call xvv_initop (out, 0, TY_INT)
O_VALI(out) = lval
case LEX_HEX:
junk = gctol (Memc, ip, lval, 16)
call xvv_initop (out, 0, TY_INT)
O_VALI(out) = lval
case LEX_REAL:
ip_start = ip
nchars = gctod (Memc, ip, dval)
call strcpy (Memc[ip], numbuf, min(nchars,MAX_DIGITS))
dtype = TY_REAL
if (stridxs ("dD", numbuf) > 0 || nchars > NDIGITS_RP+3)
dtype = TY_DOUBLE
call xvv_initop (out, 0, dtype)
if (dtype == TY_REAL) {
if (IS_INDEFD (dval))
O_VALR(out) = INDEFR
else
O_VALR(out) = dval
} else {
if (IS_INDEFD (dval))
O_VALD(out) = INDEFD
else
O_VALD(out) = dval
}
default:
goto ident_
}
return (CONSTANT)
case '\'', '"':
# Return a string constant.
ip_start = ip + 1
for (ip=ip+1; Memc[ip] != ch && Memc[ip] != EOS; ip=ip+1)
;
nchars = ip - ip_start
if (Memc[ip] == EOS)
call xvv_error ("missing closing quote in string constant")
else
ip = ip + 1
call xvv_initop (out, nchars, TY_CHAR)
call strcpy (Memc[ip_start], O_VALC(out), nchars)
return (CONSTANT)
case '+':
token = PLUS
case '-':
token = MINUS
case '*':
if (Memc[ip+1] == '*') {
ip = ip + 1
token = EXPON
} else
token = STAR
case '/':
if (Memc[ip+1] == '/') {
ip = ip + 1
token = CONCAT
} else
token = SLASH
case '?':
if (Memc[ip+1] == '=') {
ip = ip + 1
token = SE
} else
token = QUEST
case ':':
token = COLON
case '@':
token = AT
case '<':
if (Memc[ip+1] == '=') {
ip = ip + 1
token = LE
} else
token = LT
case '>':
if (Memc[ip+1] == '=') {
ip = ip + 1
token = GE
} else
token = GT
case '!':
if (Memc[ip+1] == '=') {
ip = ip + 1
token = NE
} else
token = LNOT
case '=':
if (Memc[ip+1] == '=') {
ip = ip + 1
token = EQ
} else
token = EQ
case '&':
if (Memc[ip+1] == '&') {
ip = ip + 1
token = LAND
} else
token = BAND
case '|':
if (Memc[ip+1] == '|') {
ip = ip + 1
token = LOR
} else
token = BOR
case '^':
token = BXOR
case '~':
token = BNOT
case '(', ')', ',':
token = ch
default:
if (ch == '\n')
token = NEWLINE
else if (ch == EOS)
token = YYEOS
else {
# Anything we don't understand is assumed to be an identifier.
goto ident_
}
}
ip = ip + 1
return (token)
end
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