43 #define getchr(ex)	(*(ex)->nextchr++)  argument
44 #define peekchr(ex)	(*(ex)->nextchr)  argument
45 #define ungetchr(ex)	((ex)->nextchr--)  argument
47 #define error(ex,msg)	return(seterror(ex,msg))  argument
63 seterror(register Expr_t* ex, char* msg)  in seterror()  argument
65 	if (!ex->errmsg) ex->errmsg = msg;  in seterror()
66 	ex->errchr = ex->nextchr;  in seterror()
67 	ex->nextchr = "";  in seterror()
76 expr(register Expr_t* ex, register int precedence)  in expr()  argument
84 	while (c = getchr(ex), isspace(c));  in expr()
88 		ungetchr(ex);  in expr()
90 		error(ex, "more tokens expected");  in expr()
92 		n = -expr(ex, 13);  in expr()
95 		n = expr(ex, 13);  in expr()
98 		n = !expr(ex, 13);  in expr()
101 		n = ~expr(ex, 13);  in expr()
104 		ungetchr(ex);  in expr()
111 		switch (c = getchr(ex))  in expr()
116 			if (!precedence) error(ex, "too many )'s");  in expr()
119 			n = expr(ex, 1);  in expr()
120 			if (getchr(ex) != ')')  in expr()
122 				ungetchr(ex);  in expr()
123 				error(ex, "closing ) expected");  in expr()
126 			if (operand) error(ex, "operator expected");  in expr()
131 			if (peekchr(ex) == ':')  in expr()
133 				getchr(ex);  in expr()
134 				x = expr(ex, 2);  in expr()
139 				x = expr(ex, 2);  in expr()
140 				if (getchr(ex) != ':')  in expr()
142 					ungetchr(ex);  in expr()
143 					error(ex, ": expected for ? operator");  in expr()
148 					expr(ex, 2);  in expr()
150 				else n = expr(ex, 2);  in expr()
156 			if (peekchr(ex) == '|')  in expr()
159 				getchr(ex);  in expr()
160 				x = expr(ex, 3);  in expr()
166 				x = expr(ex, 5);  in expr()
172 			x = expr(ex, 6);  in expr()
176 			if (peekchr(ex) == '&')  in expr()
179 				getchr(ex);  in expr()
180 				x = expr(ex, 4);  in expr()
186 				x = expr(ex, 7);  in expr()
192 			if (peekchr(ex) != '=') error(ex, "operator syntax error");  in expr()
194 			getchr(ex);  in expr()
195 			x = expr(ex, 8);  in expr()
201 			if (peekchr(ex) == c)  in expr()
204 				getchr(ex);  in expr()
205 				x = expr(ex, 10);  in expr()
212 				if (peekchr(ex) == '=')  in expr()
214 					getchr(ex);  in expr()
215 					x = expr(ex, 9);  in expr()
221 					x = expr(ex, 9);  in expr()
230 			x = expr(ex, 11);  in expr()
238 			x = expr(ex, 12);  in expr()
240 			else if (x == 0) error(ex, "divide by zero");  in expr()
246 			pos = --ex->nextchr;  in expr()
247 			if (isdigit(c)) n = strton(ex->nextchr, &ex->nextchr, NiL, 0);  in expr()
248 			else if (ex->convert) n = (*ex->convert)(ex->nextchr, &ex->nextchr, ex->handle);  in expr()
249 			if (ex->nextchr == pos) error(ex, "syntax error");  in expr()
252 		if (ex->errmsg) return(0);  in expr()
253 		if (!operand) error(ex, "operand expected");  in expr()
256 	ungetchr(ex);  in expr()
257 	if (!operand) error(ex, "operand expected");  in expr()
277 	Expr_t	ex;  in strexpr()  local
279 	ex.nextchr = (char*)s;  in strexpr()
280 	ex.errmsg = 0;  in strexpr()
281 	ex.convert = convert;  in strexpr()
282 	ex.handle = handle;  in strexpr()
283 	n = expr(&ex, 0);  in strexpr()
284 	if (peekchr(&ex) == ':')  in strexpr()
285 		seterror(&ex, "invalid use of :");  in strexpr()
286 	if (ex.errmsg)  in strexpr()
288 		if (convert) (*convert)(NiL, &ex.errmsg, handle);  in strexpr()
289 		ex.nextchr = ex.errchr;  in strexpr()
292 	if (end) *end = ex.nextchr;  in strexpr()