AT_DATA([[input.y]],
[[%{
-#include <stdio.h>
-#include <stdlib.h>
-static void yyerror (const char *msg);
-static int yylex (void);
+# include <stdio.h>
+# include <stdlib.h>
+ static void yyerror (const char *msg);
+ static int yylex (void);
+# define YYDEBUG 1
+# define YYERROR_VERBOSE 1
%}
%%
exp: { putchar ('0'); }
AT_CHECK([bison input.y -d -v -o input.c])
AT_CHECK([$CC $CFLAGS $CPPFLAGS input.c -o input], 0, [], [ignore])
-AT_CHECK([input], 0,
+AT_CHECK([./input], 0,
[[0123456789
]])
AT_CLEANUP
+
+
+
+## ---------------- ##
+## Exotic Dollars. ##
+## ---------------- ##
+
+AT_SETUP([Exotic Dollars])
+
+AT_DATA([[input.y]],
+[[%{
+# include <stdio.h>
+# include <stdlib.h>
+ static void yyerror (const char *msg);
+ static int yylex (void);
+# define YYDEBUG 1
+# define YYERROR_VERBOSE 1
+%}
+
+%union
+{
+ int val;
+};
+
+%type <val> a_1 a_2 a_4 a_5
+ sum_of_the_five_previous_values
+
+%%
+exp: a_1 a_2 { $<val>$ = 3; } a_4 a_5 sum_of_the_five_previous_values
+ {
+ printf ("%d\n", $6);
+ }
+;
+a_1: { $$ = 1; };
+a_2: { $$ = 2; };
+a_4: { $$ = 4; };
+a_5: { $$ = 5; };
+
+sum_of_the_five_previous_values:
+ {
+ $$ = $<val>0 + $<val>-1 + $<val>-2 + $<val>-3 + $<val>-4;
+ }
+;
+
+%%
+static int
+yylex (void)
+{
+ return EOF;
+}
+
+static void
+yyerror (const char *msg)
+{
+ fprintf (stderr, "%s\n", msg);
+}
+
+int
+main (void)
+{
+ return yyparse ();
+}
+]])
+
+AT_CHECK([bison input.y -d -v -o input.c])
+AT_CHECK([$CC $CFLAGS $CPPFLAGS input.c -o input], 0, [], [ignore])
+AT_CHECK([./input], 0,
+[[15
+]])
+
+AT_CLEANUP
+
+
+
+## ------------- ##
+## Destructors. ##
+## ------------- ##
+
+AT_SETUP([Destructors])
+
+# Make sure complex $n work.
+
+AT_DATA([[input.y]],
+[[%{
+#include <stdio.h>
+#include <stdlib.h>
+#include <assert.h>
+
+#define YYERROR_VERBOSE 1
+#define YYDEBUG 1
+#define YYPRINT yyprint
+%}
+%verbose
+%union
+{
+ int ival;
+}
+%type <ival> 'x' thing line input
+%destructor { printf ("Freeing input %d from %d\n", $$, @$.first_line); } input
+%destructor { printf ("Freeing line %d from %d\n", $$, @$.first_line); } line
+%destructor { printf ("Freeing thing %d from %d\n", $$, @$.first_line); } thing
+%destructor { printf ("Freeing 'x' %d from %d\n", $$, @$.first_line); } 'x'
+
+%{
+static int yylex (void);
+static void yyerror (const char *msg);
+static void yyprint (FILE *out, int num, YYSTYPE val);
+%}
+
+
+%%
+input:
+ /* Nothing. */
+ {
+ $$ = 0;
+ printf ("input(%d): /* Nothing */';'\n", $$);
+ }
+| line input /* Right recursive to load the stack so that popping at
+ EOF can be exercised. */
+ {
+ $$ = 2;
+ printf ("input(%d): line(%d) input(%d)';'\n", $$, $1, $2);
+ }
+;
+
+line:
+ thing thing thing ';'
+ {
+ $$ = $1;
+ printf ("line(%d): thing(%d) thing(%d) thing(%d) ';'\n", $$, $1, $2, $3);
+ }
+| thing thing ';'
+ {
+ $$ = $1;
+ printf ("line(%d): thing(%d) thing(%d) ';'\n", $$, $1, $2);
+ }
+| thing ';'
+ {
+ $$ = $1;
+ printf ("line(%d): thing(%d) ';'\n", $$, $1);
+ }
+| error ';'
+ {
+ $$ = -1;
+ printf ("line(%d): error ';'\n", $$);
+ }
+;
+
+thing:
+ 'x'
+ {
+ $$ = $1;
+ printf ("thing(%d): 'x'(%d)\n", $$, $1);
+ }
+;
+%%
+static int
+yylex (void)
+{
+ static const unsigned int input[] =
+ {
+ /* Exericise the discarding of stack top and input until `error'
+ can be reduced. */
+ 'x', 'x', 'x', 'x', 'x', 'x', ';',
+
+ /* Load the stack and provoke an error that cannot be caught be
+ the grammar, and check that the stack is cleared. */
+ 'x', 'x', ';',
+ 'x', ';',
+ 'y'
+ };
+ static int counter = 0;
+
+ if (counter < (sizeof(input) / sizeof (input[0])))
+ {
+ yylval.ival = counter;
+ printf ("sending: '%c'(%d)\n", input[counter], counter);
+ /* As in BASIC, line numbers go from 10 to 10. */
+ yylloc.first_line = 10 * counter;
+ return input[counter++];
+ }
+ else
+ {
+ printf ("sending: EOF\n");
+ return EOF;
+ }
+}
+
+static void
+yyerror (const char *msg)
+{
+ fprintf (stdout, "%d: %s\n", yylloc.first_line, msg);
+}
+
+static void
+yyprint (FILE *out, int num, YYSTYPE val)
+{
+ fprintf (out, " = %d", val.ival);
+}
+
+int
+main (void)
+{
+ yydebug = !!getenv ("YYDEBUG");
+ if (yyparse ())
+ {
+ fprintf (stdout, "Parsing FAILED.\n");
+ exit (1);
+ }
+ fprintf (stdout, "Successful parse.\n");
+ return 0;
+}
+]])
+
+AT_CHECK([bison input.y --location -d -v -o input.c])
+AT_CHECK([$CC $CFLAGS $CPPFLAGS input.c -o input], 0, [], [ignore])
+AT_CHECK([./input], 1,
+[[sending: 'x'(0)
+thing(0): 'x'(0)
+sending: 'x'(1)
+thing(1): 'x'(1)
+sending: 'x'(2)
+thing(2): 'x'(2)
+sending: 'x'(3)
+30: parse error, unexpected 'x', expecting ';'
+Freeing thing 2 from 20
+Freeing thing 1 from 10
+Freeing thing 0 from 0
+Freeing 'x' 3 from 30
+sending: 'x'(4)
+Freeing 'x' 4 from 40
+sending: 'x'(5)
+Freeing 'x' 5 from 50
+sending: ';'(6)
+line(-1): error ';'
+sending: 'x'(7)
+thing(7): 'x'(7)
+sending: 'x'(8)
+thing(8): 'x'(8)
+sending: ';'(9)
+line(7): thing(7) thing(8) ';'
+sending: 'x'(10)
+thing(10): 'x'(10)
+sending: ';'(11)
+line(10): thing(10) ';'
+sending: 'y'(12)
+120: parse error, unexpected $undefined., expecting $ or error or 'x'
+sending: EOF
+Freeing line 10 from 100
+Freeing line 7 from 70
+Freeing line -1 from 50
+Parsing FAILED.
+]])
+
+AT_CLEANUP