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SF patch #1355913, PEP 341 - Unification of try/except and try/finally

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Modified since ast-arenas was implemented.
This commit is contained in:
Neal Norwitz 2005-12-17 21:33:47 +00:00
parent adb69fcdff
commit f599f424a2
5 changed files with 265 additions and 59 deletions
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116
Python/ast.c
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@ -2597,66 +2597,78 @@ ast_for_except_clause(struct compiling *c, const node *exc, node *body)
static stmt_ty
ast_for_try_stmt(struct compiling *c, const node *n)
{
const int nch = NCH(n);
int n_except = (nch - 3)/3;
asdl_seq *body, *orelse = NULL, *finally = NULL;
REQ(n, try_stmt);
if (TYPE(CHILD(n, 3)) == NAME) {/* must be 'finally' */
/* try_stmt: 'try' ':' suite 'finally' ':' suite) */
asdl_seq *s1, *s2;
s1 = ast_for_suite(c, CHILD(n, 2));
if (!s1)
return NULL;
s2 = ast_for_suite(c, CHILD(n, 5));
if (!s2) {
return NULL;
}
return TryFinally(s1, s2, LINENO(n), c->c_arena);
}
else if (TYPE(CHILD(n, 3)) == except_clause) {
/* try_stmt: ('try' ':' suite (except_clause ':' suite)+
['else' ':' suite]
*/
asdl_seq *suite_seq1, *suite_seq2;
asdl_seq *handlers;
int i, has_else = 0, n_except = NCH(n) - 3;
if (TYPE(CHILD(n, NCH(n) - 3)) == NAME) {
has_else = 1;
n_except -= 3;
}
n_except /= 3;
handlers = asdl_seq_new(n_except, c->c_arena);
if (!handlers)
return NULL;
for (i = 0; i < n_except; i++) {
excepthandler_ty e = ast_for_except_clause(c,
CHILD(n, 3 + i * 3),
CHILD(n, 5 + i * 3));
if (!e) {
return NULL;
}
asdl_seq_SET(handlers, i, e);
}
body = ast_for_suite(c, CHILD(n, 2));
if (body == NULL)
return NULL;
suite_seq1 = ast_for_suite(c, CHILD(n, 2));
if (!suite_seq1) {
return NULL;
}
if (has_else) {
suite_seq2 = ast_for_suite(c, CHILD(n, NCH(n) - 1));
if (!suite_seq2) {
return NULL;
}
}
else
suite_seq2 = NULL;
if (TYPE(CHILD(n, nch - 3)) == NAME) {
if (strcmp(STR(CHILD(n, nch - 3)), "finally") == 0) {
if (nch >= 9 && TYPE(CHILD(n, nch - 6)) == NAME) {
/* we can assume it's an "else",
because nch >= 9 for try-else-finally and
it would otherwise have a type of except_clause */
orelse = ast_for_suite(c, CHILD(n, nch - 4));
if (orelse == NULL)
return NULL;
n_except--;
}
return TryExcept(suite_seq1, handlers, suite_seq2, LINENO(n),
c->c_arena);
finally = ast_for_suite(c, CHILD(n, nch - 1));
if (finally == NULL)
return NULL;
n_except--;
}
else {
/* we can assume it's an "else",
otherwise it would have a type of except_clause */
orelse = ast_for_suite(c, CHILD(n, nch - 1));
if (orelse == NULL)
return NULL;
n_except--;
}
}
else {
else if (TYPE(CHILD(n, nch - 3)) != except_clause) {
ast_error(n, "malformed 'try' statement");
return NULL;
}
if (n_except > 0) {
int i;
stmt_ty except_st;
/* process except statements to create a try ... except */
asdl_seq *handlers = asdl_seq_new(n_except, c->c_arena);
if (handlers == NULL)
return NULL;
for (i = 0; i < n_except; i++) {
excepthandler_ty e = ast_for_except_clause(c, CHILD(n, 3 + i * 3),
CHILD(n, 5 + i * 3));
if (!e)
return NULL;
asdl_seq_SET(handlers, i, e);
}
except_st = TryExcept(body, handlers, orelse, LINENO(n), c->c_arena);
if (!finally)
return except_st;
/* if a 'finally' is present too, we nest the TryExcept within a
TryFinally to emulate try ... except ... finally */
body = asdl_seq_new(1, c->c_arena);
if (body == NULL)
return NULL;
asdl_seq_SET(body, 0, except_st);
}
/* must be a try ... finally (except clauses are in body, if any exist) */
assert(finally != NULL);
return TryFinally(body, finally, LINENO(n), c->c_arena);
}
static stmt_ty