According to previous discussion about Sweet expression, we should treat
curly-brackets as delimiter, say:
{+ 1 1} ==> 2
This patch added an option to read-option to enable this. And the patch
will cause Guile treats curly-brackets as delimiter in default.
We don't see any harm for this till now. But one may disable it with
read-option as will.
Regards.
From 289a58122780e77968cf3e0d2ade1f786d344b1d Mon Sep 17 00:00:00 2001
From: NalaGinrut <nalagin...@gmail.com>
Date: Tue, 13 Mar 2012 13:53:05 +0800
Subject: [PATCH 1/2] add SCM_CURLY_BRACKETS_P
---
libguile/private-options.h | 2 +-
1 files changed, 1 insertions(+), 1 deletions(-)
diff --git a/libguile/private-options.h b/libguile/private-options.h
index 9d2d43c..637a8a4 100644
--- a/libguile/private-options.h
+++ b/libguile/private-options.h
@@ -67,7 +67,7 @@ SCM_INTERNAL scm_t_option scm_read_opts[];
#define SCM_R6RS_ESCAPES_P scm_read_opts[4].val
#define SCM_SQUARE_BRACKETS_P scm_read_opts[5].val
#define SCM_HUNGRY_EOL_ESCAPES_P scm_read_opts[6].val
-
+#define SCM_CURLY_BRACKETS_P scm_read_opts[7].val
#define SCM_N_READ_OPTIONS 6
#endif /* PRIVATE_OPTIONS */
--
1.7.0.4
From 5ee33a6a4516b24bef365dc441f563c129fb602a Mon Sep 17 00:00:00 2001
From: NalaGinrut <nalagin...@gmail.com>
Date: Tue, 13 Mar 2012 13:54:03 +0800
Subject: [PATCH 2/2] treat curly-brackets as delimiter in default
---
libguile/read.c | 19 ++++++++++++++++---
1 files changed, 16 insertions(+), 3 deletions(-)
diff --git a/libguile/read.c b/libguile/read.c
index bbaf3f6..57f35e5 100644
--- a/libguile/read.c
+++ b/libguile/read.c
@@ -78,6 +78,8 @@ scm_t_option scm_read_opts[] = {
"Treat `[' and `]' as parentheses, for R6RS compatibility."},
{ SCM_OPTION_BOOLEAN, "hungry-eol-escapes", 0,
"In strings, consume leading whitespace after an escaped end-of-line."},
+ { SCM_OPTION_BOOLEAN, "curly-brackets", 1,
+ "Treat `{' and `}' as parentheses, for Sweet-Exp compatibility."},
{ 0, },
};
@@ -186,7 +188,8 @@ scm_i_read_hash_procedures_set_x (SCM value)
#define CHAR_IS_R5RS_DELIMITER(c) \
(CHAR_IS_BLANK (c) \
|| (c == ')') || (c == '(') || (c == ';') || (c == '"') \
- || (SCM_SQUARE_BRACKETS_P && ((c == '[') || (c == ']'))))
+ || (SCM_SQUARE_BRACKETS_P && ((c == '[') || (c == ']'))) \
+ || (SCM_CURLY_BRACKETS_P && ((c == '{') || (c == '}'))))
#define CHAR_IS_DELIMITER CHAR_IS_R5RS_DELIMITER
@@ -373,7 +376,7 @@ scm_read_sexp (scm_t_wchar chr, SCM port)
{
int c;
SCM tmp, tl, ans = SCM_EOL;
- const int terminating_char = ((chr == '[') ? ']' : ')');
+ const int terminating_char = ((chr == '[') ? ']' : ((chr == '{') ? '}' : ')'));
/* Need to capture line and column numbers here. */
long line = SCM_LINUM (port);
@@ -405,7 +408,9 @@ scm_read_sexp (scm_t_wchar chr, SCM port)
{
SCM new_tail;
- if (c == ')' || (SCM_SQUARE_BRACKETS_P && c == ']'))
+ if (c == ')'
+ || (SCM_SQUARE_BRACKETS_P && c == ']')
+ || (SCM_CURLY_BRACKETS_P && c == '}'))
scm_i_input_error (FUNC_NAME, port,
"in pair: mismatched close paren: ~A",
scm_list_1 (SCM_MAKE_CHAR (c)));
@@ -1449,6 +1454,10 @@ scm_read_expression (SCM port)
if (!SCM_SQUARE_BRACKETS_P)
return (scm_read_mixed_case_symbol (chr, port));
/* otherwise fall through */
+ case '{':
+ if (!SCM_CURLY_BRACKETS_P)
+ return (scm_read_mixed_case_symbol (chr, port));
+ /* otherwise fall through */
case '(':
return (scm_read_sexp (chr, port));
case '"':
@@ -1475,6 +1484,10 @@ scm_read_expression (SCM port)
if (SCM_SQUARE_BRACKETS_P)
scm_i_input_error (FUNC_NAME, port, "unexpected \"]\"", SCM_EOL);
/* otherwise fall through */
+ case '}':
+ if (SCM_CURLY_BRACKETS_P)
+ scm_i_input_error (FUNC_NAME, port, "unexpected \"}\"", SCM_EOL);
+ /* otherwise fall through */
case EOF:
return SCM_EOF_VAL;
case ':':
--
1.7.0.4
