3 #include "ly-module.hh"
4 #include "lily-guile.hh"
6 #include "paper-book.hh"
7 #include "parse-scm.hh"
9 #include "source-file.hh"
11 /* Pass string to scm parser, evaluate one expression.
12 Return result value and #chars read.
14 Thanks to Gary Houston <ghouston@freewire.co.uk> */
16 internal_ly_parse_scm (Parse_start * ps)
18 Source_file* sf =ps->start_location_.source_file_;
19 SCM port = sf->get_port ();
21 int off = ps->start_location_.defined_str0_ - sf->to_str0();
23 scm_seek (port, scm_long2num (off), scm_long2num (SEEK_SET));
24 SCM from = scm_ftell (port);
27 SCM answer = SCM_UNSPECIFIED;
29 /* Read expression from port */
30 if (!SCM_EOF_OBJECT_P (form = scm_read (port)))
32 answer = scm_primitive_eval (form);
35 /* Reset read_buf for scm_ftell.
36 Shouldn't scm_read () do this for us? */
37 scm_fill_input (port);
38 SCM to = scm_ftell (port);
39 ps->nchars = ly_scm2int (to) - ly_scm2int (from);
41 /* Don't close the port here; if we re-enter this function via a
42 continuation, then the next time we enter it, we'll get an error.
43 It's a string port anyway, so there's no advantage to closing it
45 // scm_close_port (port);
51 catch_protected_parse_body (void *p)
53 Parse_start *ps = (Parse_start*) p;
54 return internal_ly_parse_scm (ps);
58 safe_catch_protected_parse_body (void *p)
60 Parse_start *ps = (Parse_start*) p;
61 return internal_ly_parse_scm (ps);
65 parse_handler (void * data, SCM tag, SCM args)
67 Parse_start* ps = (Parse_start*) data;
68 (void) tag; // prevent warning
70 ps->start_location_.error (_("GUILE signaled an error for the expression beginning here"));
72 if (scm_ilength (args) > 2)
73 scm_display_error_message (ly_cadr (args), ly_caddr (args), scm_current_error_port ());
76 The following is a kludge; we should probably search for
77 [a-z][0-9] (a note), and start before that.
85 Do some magical incantations: if not, lily will exit on the first
86 GUILE error, leaving no location trace.
90 #if GUILE_MINOR_VERSION < 7
91 #define READ_ERROR "misc-error"
93 #define READ_ERROR "read-error"
97 protected_ly_parse_scm (Parse_start *ps)
99 return scm_internal_catch (ly_symbol2scm (READ_ERROR),
100 &catch_protected_parse_body,
102 &parse_handler, (void*) ps);
105 bool parse_protect_global = true;
107 /* Try parsing. Upon failure return SCM_UNDEFINED. */
109 ly_parse_scm (char const* s, int *n, Input i, bool safe)
113 ps.start_location_ = i;
115 SCM ans = parse_protect_global ? protected_ly_parse_scm (&ps)
116 : internal_ly_parse_scm (&ps);