diff options
| author | Keith Packard <keithp@keithp.com> | 2016-11-10 23:25:56 -0800 |
|---|---|---|
| committer | Keith Packard <keithp@keithp.com> | 2017-02-20 11:16:50 -0800 |
| commit | 92cdc0cf0e80c1ff3f31cce20fc2b9bda86e3638 (patch) | |
| tree | 2480c8bc3baba89873aea4061796a91522a7f5fb /src/lisp/ao_lisp_read.c | |
| parent | fb710f7f4f24f74ac3d45fcc423803384d986bb2 (diff) | |
altos/lisp: Make read() return eof atom on end of file
Also make it an exception to hit eof in the middle of an sexpr.
Signed-off-by: Keith Packard <keithp@keithp.com>
Diffstat (limited to 'src/lisp/ao_lisp_read.c')
| -rw-r--r-- | src/lisp/ao_lisp_read.c | 18 |
1 files changed, 14 insertions, 4 deletions
diff --git a/src/lisp/ao_lisp_read.c b/src/lisp/ao_lisp_read.c index 3a2ef7f1..7a5751ce 100644 --- a/src/lisp/ao_lisp_read.c +++ b/src/lisp/ao_lisp_read.c @@ -12,6 +12,7 @@ * General Public License for more details. */ +#define DBG_EVAL 0 #include "ao_lisp.h" #include "ao_lisp_read.h" @@ -270,7 +271,7 @@ lex(void) for (;;) { c = lexc(); if (lex_class & ENDOFFILE) - return AO_LISP_NIL; + return END; if (lex_class & WHITE) continue; @@ -278,7 +279,7 @@ lex(void) if (lex_class & COMMENT) { while ((c = lexc()) != '\n') { if (lex_class & ENDOFFILE) - return AO_LISP_NIL; + return END; } continue; } @@ -364,6 +365,8 @@ static struct ao_lisp_cons *read_stack; static int push_read_stack(int cons, int in_quote) { + DBGI("push read stack %p %d\n", read_cons, in_quote); + DBG_IN(); if (cons) { read_stack = ao_lisp_cons_cons(ao_lisp_cons_poly(read_cons), ao_lisp_cons_cons(ao_lisp_int_poly(in_quote), @@ -394,6 +397,8 @@ pop_read_stack(int cons) read_cons_tail = 0; read_stack = 0; } + DBG_OUT(); + DBGI("pop read stack %p %d\n", read_cons, in_quote); return in_quote; } @@ -413,6 +418,7 @@ ao_lisp_read(void) been_here = 1; } parse_token = lex(); + DBGI("token %d (%s)\n", parse_token, token_string); cons = 0; in_quote = 0; @@ -424,12 +430,15 @@ ao_lisp_read(void) cons++; in_quote = 0; parse_token = lex(); + DBGI("token %d (%s)\n", parse_token, token_string); } switch (parse_token) { - case ENDOFFILE: + case END: default: - v = AO_LISP_NIL; + if (cons) + ao_lisp_error(AO_LISP_EOF, "unexpected end of file"); + return _ao_lisp_atom_eof; break; case NAME: atom = ao_lisp_atom_intern(token_string); @@ -490,6 +499,7 @@ ao_lisp_read(void) } parse_token = lex(); + DBGI("token %d (%s)\n", parse_token, token_string); } return v; } |