first implementation

1 files changed, 82 insertions, 0 deletions

diff --git a/Try.xs b/Try.xs
new file mode 100644
index 0000000..59f9b64
--- /dev/null
+++ b/Try.xs
@@ -0,0 +1,82 @@
+#include "EXTERN.h"
+#include "perl.h"
+#include "callparser1.h"
+#include "XSUB.h"
+
+static int check_keyword(const char *keyword)
+{
+    STRLEN len;
+
+    len = strlen(keyword);
+    if (PL_parser->bufend - PL_parser->bufptr < len) {
+        return 0;
+    }
+
+    if (strnNE(PL_parser->bufptr, keyword, len)) {
+        return 0;
+    }
+
+    if (PL_parser->bufptr + len != PL_parser->bufend
+        && isALNUM(*(PL_parser->bufptr + len))) {
+        return 0;
+    }
+
+    lex_read_to(PL_parser->bufptr + len);
+
+    return 1;
+}
+
+static OP *parse_try(pTHX_ GV *namegv, SV *psobj, U32 *flagsp)
+{
+    OP *try, *catch, *finally, *ret;
+    I32 floor;
+
+    *flagsp |= CALLPARSER_STATEMENT;
+
+    lex_read_space(0);
+    if (*(PL_parser->bufptr) != '{') {
+        croak("syntax error");
+    }
+    floor = start_subparse(0, CVf_ANON);
+    try = newANONSUB(floor, NULL, parse_block(0));
+
+    lex_read_space(0);
+    if (check_keyword("catch")) {
+        lex_read_space(0);
+        if (*(PL_parser->bufptr) != '{') {
+            croak("syntax error");
+        }
+        floor = start_subparse(0, CVf_ANON);
+        catch = newANONSUB(floor, NULL, parse_block(0));
+    }
+    else {
+        catch = newOP(OP_UNDEF, 0);
+    }
+
+    lex_read_space(0);
+    if (check_keyword("finally")) {
+        lex_read_space(0);
+        if (*(PL_parser->bufptr) != '{') {
+            croak("syntax error");
+        }
+        floor = start_subparse(0, CVf_ANON);
+        finally = newANONSUB(floor, NULL, parse_block(0));
+    }
+    else {
+        finally = newOP(OP_UNDEF, 0);
+    }
+
+    ret = newLISTOP(OP_LIST, 0, try, catch);
+    op_append_elem(OP_LIST, ret, finally);
+
+    return ret;
+}
+
+MODULE = Try  PACKAGE = Try
+
+PROTOTYPES: DISABLE
+
+BOOT:
+{
+    cv_set_call_parser(get_cv("Try::try", 0), parse_try, &PL_sv_undef);
+}