[Qemu-devel] [PATCH] CODING_STYLE: don't allow non-indented statements after if/else blocks
Rationale: The following code is difficult to read, but allowed by the
current coding style.
if (a == 5) printf(a was 5.\n);
else if (a == 6) printf(a was 6.\n);
else printf(a was something else entirely.\n);
Signed-off-by: Aurelien Jarno aurel...@aurel32.net
---
CODING_STYLE | 10 +-
1 files changed, 5 insertions(+), 5 deletions(-)
diff --git a/CODING_STYLE b/CODING_STYLE
index a579cb1..3ffbc3d 100644
--- a/CODING_STYLE
+++ b/CODING_STYLE
@@ -51,11 +51,11 @@ QEMU coding style.
4. Block structure
-Every indented statement is braced; even if the block contains just one
-statement. The opening brace is on the line that contains the control
-flow statement that introduces the new block; the closing brace is on the
-same line as the else keyword, or on a line by itself if there is no else
-keyword. Example:
+Every control flow statement is followed by a new indented and braced
+block; even if the block contains just one statement. The opening brace
+is on the line that contains the control flow statement that introduces
+the new block; the closing brace is on the same line as the else keyword,
+or on a line by itself if there is no else keyword. Example:
if (a == 5) {
printf(a was 5.\n);
--
1.6.1.3
Re: [Qemu-devel] [PATCH] CODING_STYLE: don't allow non-indented statements after if/else blocks
On Mon, Oct 26, 2009 at 8:26 AM, Aurelien Jarno aurel...@aurel32.net wrote:
Rationale: The following code is difficult to read, but allowed by the
current coding style.
Fully agree.
+Every control flow statement is followed by a new indented and braced
+block; even if the block contains just one statement. The opening brace
+is on the line that contains the control flow statement that introduces
+the new block; the closing brace is on the same line as the else keyword,
+or on a line by itself if there is no else keyword. Example:
I think an exception should be granted for else if case, otherwise
the style would require braces around if, like:
if (a == 5) {
printf(a was 5.\n);
} else {
if (a == 6) {
printf(a was 6.\n);
}
} else {
printf(a was something else entirely.\n);
}
Picking nits: while is a control flow statement, even in do {}
while statement and then it would illegal to require a braced block
after the while statement.
Re: [Qemu-devel] [PATCH] CODING_STYLE: don't allow non-indented statements after if/else blocks
On Mon, Oct 26, 2009 at 06:02:52PM +0200, Blue Swirl wrote:
On Mon, Oct 26, 2009 at 8:26 AM, Aurelien Jarno aurel...@aurel32.net wrote:
Rationale: The following code is difficult to read, but allowed by the
current coding style.
Fully agree.
+Every control flow statement is followed by a new indented and braced
+block; even if the block contains just one statement. The opening brace
+is on the line that contains the control flow statement that introduces
+the new block; the closing brace is on the same line as the else keyword,
+or on a line by itself if there is no else keyword. Example:
I think an exception should be granted for else if case, otherwise
the style would require braces around if, like:
if (a == 5) {
printf(a was 5.\n);
} else {
if (a == 6) {
printf(a was 6.\n);
}
} else {
printf(a was something else entirely.\n);
}
Picking nits: while is a control flow statement, even in do {}
while statement and then it would illegal to require a braced block
after the while statement.
Good point. Please find another try below:
From: Aurelien Jarno aurel...@aurel32.net
Rationale: The following code is difficult to read:
if (a == 5) printf(a was 5.\n);
else if (a == 6) printf(a was 6.\n);
else printf(a was something else entirely.\n);
Signed-off-by: Aurelien Jarno aurel...@aurel32.net
---
CODING_STYLE | 12 +++-
1 files changed, 7 insertions(+), 5 deletions(-)
diff --git a/CODING_STYLE b/CODING_STYLE
index a579cb1..c17c3f3 100644
--- a/CODING_STYLE
+++ b/CODING_STYLE
@@ -51,11 +51,13 @@ QEMU coding style.
4. Block structure
-Every indented statement is braced; even if the block contains just one
-statement. The opening brace is on the line that contains the control
-flow statement that introduces the new block; the closing brace is on the
-same line as the else keyword, or on a line by itself if there is no else
-keyword. Example:
+Every control flow statement is followed by a new indented and braced
+block, except if it is followed by another control flow statement (else
+if) or by a condition (do {} while ()); even if the block contains just
+one statement. The opening brace is on the line that contains the
+control flow statement that introduces the new block; the closing
+brace is on the same line as the else keyword, or on a line by itself
+if there is no else keyword. Example:
if (a == 5) {
printf(a was 5.\n);
--
1.6.1.3
--
Aurelien Jarno GPG: 1024D/F1BCDB73
aurel...@aurel32.net http://www.aurel32.net
Re: [Qemu-devel] [PATCH] CODING_STYLE: don't allow non-indented statements after if/else blocks
On Mon, Oct 26, 2009 at 10:03 PM, Aurelien Jarno aurel...@aurel32.net wrote:
On Mon, Oct 26, 2009 at 06:02:52PM +0200, Blue Swirl wrote:
On Mon, Oct 26, 2009 at 8:26 AM, Aurelien Jarno aurel...@aurel32.net wrote:
Rationale: The following code is difficult to read, but allowed by the
current coding style.
Fully agree.
+Every control flow statement is followed by a new indented and braced
+block; even if the block contains just one statement. The opening brace
+is on the line that contains the control flow statement that introduces
+the new block; the closing brace is on the same line as the else keyword,
+or on a line by itself if there is no else keyword. Example:
I think an exception should be granted for else if case, otherwise
the style would require braces around if, like:
if (a == 5) {
printf(a was 5.\n);
} else {
if (a == 6) {
printf(a was 6.\n);
}
} else {
printf(a was something else entirely.\n);
}
Picking nits: while is a control flow statement, even in do {}
while statement and then it would illegal to require a braced block
after the while statement.
Good point. Please find another try below:
From: Aurelien Jarno aurel...@aurel32.net
Rationale: The following code is difficult to read:
if (a == 5) printf(a was 5.\n);
else if (a == 6) printf(a was 6.\n);
else printf(a was something else entirely.\n);
Signed-off-by: Aurelien Jarno aurel...@aurel32.net
---
CODING_STYLE | 12 +++-
1 files changed, 7 insertions(+), 5 deletions(-)
diff --git a/CODING_STYLE b/CODING_STYLE
index a579cb1..c17c3f3 100644
--- a/CODING_STYLE
+++ b/CODING_STYLE
@@ -51,11 +51,13 @@ QEMU coding style.
4. Block structure
-Every indented statement is braced; even if the block contains just one
-statement. The opening brace is on the line that contains the control
-flow statement that introduces the new block; the closing brace is on the
-same line as the else keyword, or on a line by itself if there is no else
-keyword. Example:
+Every control flow statement is followed by a new indented and braced
+block, except if it is followed by another control flow statement (else
+if) or by a condition (do {} while ()); even if the block contains just
+one statement. The opening brace is on the line that contains the
+control flow statement that introduces the new block; the closing
+brace is on the same line as the else keyword, or on a line by itself
+if there is no else keyword. Example:
Nice try, but does it prevent this:
if (x) for (;;) do {
} while (0);
?
Maybe also break and goto can be considered control flow statements.
How about something like wherever C syntax allows potentially
ambiguous sequence of statements, braces must be used, with the
exception of 'else' followed by 'if'? Now the problem becomes
defining ambiguous sequences of statements.
Re: [Qemu-devel] [PATCH] CODING_STYLE: don't allow non-indented statements after if/else blocks
On Mon, Oct 26, 2009 at 10:20:34PM +0200, Blue Swirl wrote:
On Mon, Oct 26, 2009 at 10:03 PM, Aurelien Jarno aurel...@aurel32.net wrote:
On Mon, Oct 26, 2009 at 06:02:52PM +0200, Blue Swirl wrote:
On Mon, Oct 26, 2009 at 8:26 AM, Aurelien Jarno aurel...@aurel32.net
wrote:
Rationale: The following code is difficult to read, but allowed by the
current coding style.
Fully agree.
+Every control flow statement is followed by a new indented and braced
+block; even if the block contains just one statement. The opening brace
+is on the line that contains the control flow statement that introduces
+the new block; the closing brace is on the same line as the else
keyword,
+or on a line by itself if there is no else keyword. Example:
I think an exception should be granted for else if case, otherwise
the style would require braces around if, like:
if (a == 5) {
printf(a was 5.\n);
} else {
if (a == 6) {
printf(a was 6.\n);
}
} else {
printf(a was something else entirely.\n);
}
Picking nits: while is a control flow statement, even in do {}
while statement and then it would illegal to require a braced block
after the while statement.
Good point. Please find another try below:
From: Aurelien Jarno aurel...@aurel32.net
Rationale: The following code is difficult to read:
if (a == 5) printf(a was 5.\n);
else if (a == 6) printf(a was 6.\n);
else printf(a was something else entirely.\n);
Signed-off-by: Aurelien Jarno aurel...@aurel32.net
---
CODING_STYLE | 12 +++-
1 files changed, 7 insertions(+), 5 deletions(-)
diff --git a/CODING_STYLE b/CODING_STYLE
index a579cb1..c17c3f3 100644
--- a/CODING_STYLE
+++ b/CODING_STYLE
@@ -51,11 +51,13 @@ QEMU coding style.
4. Block structure
-Every indented statement is braced; even if the block contains just one
-statement. The opening brace is on the line that contains the control
-flow statement that introduces the new block; the closing brace is on the
-same line as the else keyword, or on a line by itself if there is no else
-keyword. Example:
+Every control flow statement is followed by a new indented and braced
+block, except if it is followed by another control flow statement (else
+if) or by a condition (do {} while ()); even if the block contains just
+one statement. The opening brace is on the line that contains the
+control flow statement that introduces the new block; the closing
+brace is on the same line as the else keyword, or on a line by itself
+if there is no else keyword. Example:
Nice try, but does it prevent this:
if (x) for (;;) do {
} while (0);
?
We should find a way to define for (;;) as a single statement.
Maybe also break and goto can be considered control flow statements.
Correct, they should be excluded from there as they don't need to be
followed by braces.
How about something like wherever C syntax allows potentially
ambiguous sequence of statements, braces must be used, with the
exception of 'else' followed by 'if'? Now the problem becomes
defining ambiguous sequences of statements.
That's the problem. We have seen that people already take advantage of
the ambiguities, as I would have never have imagined someone writing the
code in the rationale of this patch to avoid putting braces.
--
Aurelien Jarno GPG: 1024D/F1BCDB73
aurel...@aurel32.net http://www.aurel32.net
Re: [Qemu-devel] [PATCH] CODING_STYLE: don't allow non-indented statements after if/else blocks
Aurelien Jarno wrote: That's the problem. We have seen that people already take advantage of the ambiguities, as I would have never have imagined someone writing the code in the rationale of this patch to avoid putting braces. I appreciate the desire to be precise, but we aren't writing a compiler or an automated syntax checker. We're writing a set of guidelines for reasonable people to follow. If someone sets out to defeat CODING_STYLE by introducing some crazy syntax, the solution is simple--just don't take the patch. Good sense must prevail regardless of what CODING_STYLE says. Regards, Anthony Liguori
