[Top][All Lists]
[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]
Re: [PATCH] R6RS-style block comments
From: |
Andreas Rottmann |
Subject: |
Re: [PATCH] R6RS-style block comments |
Date: |
Mon, 05 Oct 2009 15:25:04 +0200 |
User-agent: |
Gnus/5.13 (Gnus v5.13) Emacs/23.1 (gnu/linux) |
address@hidden (Ludovic Courtès) writes:
> Hi,
>
> Andreas Rottmann <address@hidden> writes:
>
>> Attached is a patch that extends the read syntax to allow for #| ... |#
>> block comments.
>
> Are there objections to this patch? If no, I’ll apply it.
>
> Note that it makes the reader understand this syntax by default, not via
> a read option.
>
I have attached an updated version of the patch which should apply
cleanly against current HEAD.
From: Andreas Rottmann <address@hidden>
Subject: [PATCH] Add support for #| ... |# comments
This syntax has been added by R6RS.
---
NEWS | 5 +++++
libguile/read.c | 33 ++++++++++++++++++++-------------
2 files changed, 25 insertions(+), 13 deletions(-)
diff --git a/NEWS b/NEWS
index 66e21de..c2f3bdc 100644
--- a/NEWS
+++ b/NEWS
@@ -412,6 +412,11 @@ actually used this, this behavior may be reinstated via the
#; comments out an entire expression. See SRFI-62 or the R6RS for more
information.
+** Additional syntax for block comments
+
+#| ... |# is now accepted syntax for block comments, in addition to
+#! ... !#.
+
** `make-stack' with a tail-called procedural narrowing argument no longer
works (with compiled procedures)
diff --git a/libguile/read.c b/libguile/read.c
index 07c8d71..10ac08e 100644
--- a/libguile/read.c
+++ b/libguile/read.c
@@ -180,9 +180,9 @@ static SCM *scm_read_hash_procedures;
(((_chr) == 'e') || ((_chr) == 's') || ((_chr) == 'f') \
|| ((_chr) == 'd') || ((_chr) == 'l'))
-/* Read an SCSH block comment. */
-static inline SCM scm_read_scsh_block_comment (int chr, SCM port);
-static SCM scm_read_commented_expression (int chr, SCM port);
+/* Read an SCSH or R6RS block comment. */
+static inline SCM scm_read_block_comment (scm_t_wchar chr, SCM port);
+static SCM scm_read_commented_expression (scm_t_wchar chr, SCM port);
/* Read from PORT until a delimiter (e.g., a whitespace) is read. Return
zero if the whole token fits in BUF, non-zero otherwise. */
@@ -284,7 +284,8 @@ flush_ws (SCM port, const char *eoferr)
eoferr = "read_sharp";
goto goteof;
case '!':
- scm_read_scsh_block_comment (c, port);
+ case '|':
+ scm_read_block_comment (c, port);
break;
case ';':
scm_read_commented_expression (c, port);
@@ -963,9 +964,10 @@ scm_read_guile_bit_vector (scm_t_wchar chr, SCM port)
}
static inline SCM
-scm_read_scsh_block_comment (scm_t_wchar chr, SCM port)
+scm_read_block_comment (scm_t_wchar chr, SCM port)
{
- int bang_seen = 0;
+ int comment_char_seen = 0;
+ int comment_char = (int) chr;
/* We can use the get_byte here because there is no need to get the
locale correct when reading comments. This presumes that
@@ -976,15 +978,19 @@ scm_read_scsh_block_comment (scm_t_wchar chr, SCM port)
int c = scm_get_byte_or_eof (port);
if (c == EOF)
- scm_i_input_error ("skip_block_comment", port,
- "unterminated `#! ... !#' comment", SCM_EOL);
+ {
+ scm_i_input_error ("skip_block_comment", port,
+ "unterminated `#~A ... ~A#' comment",
+ scm_list_2 (SCM_MAKE_CHAR (comment_char),
+ SCM_MAKE_CHAR (comment_char)));
+ }
- if (c == '!')
- bang_seen = 1;
- else if (c == '#' && bang_seen)
+ if (c == comment_char)
+ comment_char_seen = 1;
+ else if (c == '#' && comment_char_seen)
break;
else
- bang_seen = 0;
+ comment_char_seen = 0;
}
return SCM_UNSPECIFIED;
@@ -1163,7 +1169,8 @@ scm_read_sharp (scm_t_wchar chr, SCM port)
case '{':
return (scm_read_extended_symbol (chr, port));
case '!':
- return (scm_read_scsh_block_comment (chr, port));
+ case '|':
+ return (scm_read_block_comment (chr, port));
case ';':
return (scm_read_commented_expression (chr, port));
case '`':
--
tg: (b25aa0b..) t/r6rs-block-comments (depends on: master)
Regards, Rotty
Re: [PATCH] R6RS-style block comments, Neil Jerram, 2009/10/06