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%option reentrant bison-bridge bison-locations
%option noyywrap
%option never-interactive
%x STRING
%x IND_STRING
%{
#include "nixexpr.hh"
#include "parser-tab.hh"
using namespace nix;
namespace nix {
static void initLoc(YYLTYPE * loc)
{
loc->first_line = loc->last_line = 1;
loc->first_column = loc->last_column = 1;
}
static void adjustLoc(YYLTYPE * loc, const char * s, size_t len)
{
loc->first_line = loc->last_line;
loc->first_column = loc->last_column;
while (len--) {
switch (*s++) {
case '\r':
if (*s == '\n') /* cr/lf */
s++;
/* fall through */
case '\n':
++loc->last_line;
loc->last_column = 1;
break;
default:
++loc->last_column;
}
}
}
static Expr * unescapeStr(SymbolTable & symbols, const char * s)
{
string t;
char c;
while ((c = *s++)) {
if (c == '\\') {
assert(*s);
c = *s++;
if (c == 'n') t += '\n';
else if (c == 'r') t += '\r';
else if (c == 't') t += '\t';
else t += c;
}
else if (c == '\r') {
/* Normalise CR and CR/LF into LF. */
t += '\n';
if (*s == '\n') s++; /* cr/lf */
}
else t += c;
}
return new ExprString(symbols.create(t));
}
}
#define YY_USER_INIT initLoc(yylloc)
#define YY_USER_ACTION adjustLoc(yylloc, yytext, yyleng);
%}
ID [a-zA-Z\_][a-zA-Z0-9\_\'\-]*
INT [0-9]+
PATH [a-zA-Z0-9\.\_\-\+]*(\/[a-zA-Z0-9\.\_\-\+]+)+
SPATH \<[a-zA-Z0-9\.\_\-\+]+(\/[a-zA-Z0-9\.\_\-\+]+)*\>
URI [a-zA-Z][a-zA-Z0-9\+\-\.]*\:[a-zA-Z0-9\%\/\?\:\@\&\=\+\$\,\-\_\.\!\~\*\']+
%%
if { return IF; }
then { return THEN; }
else { return ELSE; }
assert { return ASSERT; }
with { return WITH; }
let { return LET; }
in { return IN; }
rec { return REC; }
inherit { return INHERIT; }
or { return OR_KW; }
\.\.\. { return ELLIPSIS; }
\=\= { return EQ; }
\!\= { return NEQ; }
\<\= { return LEQ; }
\>\= { return GEQ; }
\&\& { return AND; }
\|\| { return OR; }
\-\> { return IMPL; }
\/\/ { return UPDATE; }
\+\+ { return CONCAT; }
{ID} { yylval->id = strdup(yytext); return ID; }
{INT} { errno = 0;
yylval->n = strtol(yytext, 0, 10);
if (errno != 0)
throw ParseError(format("invalid integer `%1%'") % yytext);
return INT;
}
\$\{ { return DOLLAR_CURLY; }
\" { BEGIN(STRING); return '"'; }
<STRING>([^\$\"\\]|\$[^\{\"]|\\.)+ {
/* !!! Not quite right: we want a follow restriction on
"$", it shouldn't be followed by a "{". Right now
"$\"" will be consumed as part of a string, rather
than a "$" followed by the string terminator.
Disallow "$\"" for now. */
yylval->e = unescapeStr(data->symbols, yytext);
return STR;
}
<STRING>\$\{ { BEGIN(INITIAL); return DOLLAR_CURLY; }
<STRING>\" { BEGIN(INITIAL); return '"'; }
<STRING>. return yytext[0]; /* just in case: shouldn't be reached */
\'\'(\ *\n)? { BEGIN(IND_STRING); return IND_STRING_OPEN; }
<IND_STRING>([^\$\']|\$[^\{\']|\'[^\'\$])+ {
yylval->e = new ExprIndStr(yytext);
return IND_STR;
}
<IND_STRING>\'\'\$ {
yylval->e = new ExprIndStr("$");
return IND_STR;
}
<IND_STRING>\'\'\' {
yylval->e = new ExprIndStr("''");
return IND_STR;
}
<IND_STRING>\'\'\\. {
yylval->e = unescapeStr(data->symbols, yytext + 2);
return IND_STR;
}
<IND_STRING>\$\{ { BEGIN(INITIAL); return DOLLAR_CURLY; }
<IND_STRING>\'\' { BEGIN(INITIAL); return IND_STRING_CLOSE; }
<IND_STRING>\' {
yylval->e = new ExprIndStr("'");
return IND_STR;
}
<IND_STRING>. return yytext[0]; /* just in case: shouldn't be reached */
{PATH} { yylval->path = strdup(yytext); return PATH; }
{SPATH} { yylval->path = strdup(yytext); return SPATH; }
{URI} { yylval->uri = strdup(yytext); return URI; }
[ \t\r\n]+ /* eat up whitespace */
\#[^\r\n]* /* single-line comments */
\/\*([^*]|\*[^\/])*\*\/ /* long comments */
. return yytext[0];
%%
namespace nix {
/* Horrible, disgusting hack: allow the parser to set the scanner
start condition back to STRING. Necessary in interpolations like
"foo${expr}bar"; after the close brace we have to go back to the
STRING state. */
void backToString(yyscan_t scanner)
{
struct yyguts_t * yyg = (struct yyguts_t *) scanner;
BEGIN(STRING);
}
void backToIndString(yyscan_t scanner)
{
struct yyguts_t * yyg = (struct yyguts_t *) scanner;
BEGIN(IND_STRING);
}
}
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