=head1 DESCRIPTION
-Perltidy reads a perl script and writes an indented, reformatted script.
-This document describes the parameters available for controlling this formatting.
+Perltidy reads a perl script and writes an indented, reformatted script. The
+formatting process involves converting the script into a string of tokens,
+removing any non-essential whitespace, and then rewriting the string of tokens
+with whitespace using whatever rules are specified, or defaults. This happens
+in a series of operations which can be controlled with the parameters described
+in this document.
Perltidy is a commandline frontend to the module Perl::Tidy. For documentation
describing how to call the Perl::Tidy module from other applications see the
For example, instead of B<--dump-token-types>, it would be sufficient to enter
B<--dump-tok>, or even B<--dump-t>, to uniquely identify this command.
-=head2 I/O control
+=head2 I/O Control
The following parameters concern the files which are read and written.
item for changing the default backup extension, and for eliminating the
backup file altogether.
+B<Please Note>: Writing back to the input file increases the risk of data loss
+or corruption in the event of a software or hardware malfunction. Before using
+the B<-b> parameter please be sure to have backups and verify that it works
+correctly in your environment and operating system.
+
A B<-b> flag will be ignored if input is from standard input or goes to
standard output, or if the B<-html> flag is set.
<-bext='/backup'> F<.backup> Delete if no errors
<-bext='original/'> F<.original> Delete if no errors
+=item B<-bm=s>, B<--backup-method=s>
+
+This parameter should not normally be used but is available in the event that
+problems arise as a transition is made from an older implementation of the
+backup logic to a newer implementation. The newer implementation is the
+default and is specified with B<-bm='copy'>. The older implementation is
+specified with B<-bm='move'>. The difference is that the older implementation
+made the backup by moving the input file to the backup file, and the newer
+implementation makes the backup by copying the input file. The newer
+implementation preserves the file system B<inode> value. This may avoid
+problems with other software running simultaneously. This change was made
+as part of issue B<git #103> at github.
+
=item B<-w>, B<--warning-output>
Setting B<-w> causes any non-critical warning
parameters. If this is not the case, an error message noting this is produced.
This flag has no other effect on the functioning of perltidy.
-=item B<-sal=s>, B<--sub-alias-list=s>
-
-This flag causes one or more words to be treated the same as if they were the keyword 'sub'. The string B<s> contains one or more alias words, separated by spaces or commas.
-
-For example,
-
- perltidy -sal='method fun _sub M4'
-
-will cause the perltidy to treat the words 'method', 'fun', '_sub' and 'M4' the same as if they were 'sub'. Note that if the alias words are separated by spaces then the string of words should be placed in quotes.
-
-Note that several other parameters accept a list of keywords, including 'sub' (see L<"Specifying Block Types">).
-You do not need to include any sub aliases in these lists. Just include keyword 'sub' if you wish, and all aliases are automatically included.
-
-=item B<-gal=s>, B<--grep-alias-list=s>
-
-This flag allows a code block following an external 'list operator' function to be formatted as if it followed one of the built-in keywords B<grep>, B<map> or B<sort>. The string B<s> contains the names of one or more such list operators, separated by spaces or commas.
-
-By 'list operator' is meant a function which is invoked in the form
-
- word {BLOCK} @list
-
-Perltidy tries to keep code blocks for these functions intact, since they are usually short, and does not automatically break after the closing brace since a list may follow. It also does some special handling of continuation indentation.
-
-For example, the code block arguments to functions 'My_grep' and 'My_map' can be given formatting like 'grep' with
-
- perltidy -gal='My_grep My_map'
-
-By default, the following list operators in List::Util are automatically included:
-
- all any first none notall reduce reductions
-
-Any operators specified with B<--grep-alias-list> are added to this list.
-The next parameter can be used to remove words from this default list.
-
-=item B<-gaxl=s>, B<--grep-alias-exclusion-list=s>
-
-The B<-gaxl=s> flag provides a method for removing any of the default list operators given above
-by listing them in the string B<s>. To remove all of the default operators use B<-gaxl='*'>.
-
=back
=head1 FORMATTING OPTIONS
=back
-=item B<-xs>, B<--extended-syntax>
-
-A problem with formatting Perl code is that some modules can introduce new
-syntax. This flag allows perltidy to handle certain common extensions
-to the standard syntax without complaint.
-
-For example, without this flag a structure such as the following would generate
-a syntax error and the braces would not be balanced:
-
- method deposit( Num $amount) {
- $self->balance( $self->balance + $amount );
- }
-
-For one of the extensions, module Switch::Plain, colons are marked as labels.
-If you use this module, you may want to also use the B<--nooutdent-labels> flag
-to prevent lines such as 'default:' from being outdented.
-
-This flag is enabled by default but it can be deactivated with B<-nxs>.
-Probably the only reason to deactivate this flag is to generate more diagnostic
-messages when debugging a script.
-
-For another method of handling extended syntax see the section L<"Skipping Selected Sections of Code">.
-
=item B<-io>, B<--indent-only>
This flag is used to deactivate all whitespace and line break changes
fixit($i);
}
-Use B<-nola> to not outdent labels. To control line breaks after labels see L<"bal=n, --break-after-labels=n">.
+Use B<-nola> to not outdent labels. To control line breaks after labels see L<"-bal=n, --break-after-labels=n">.
=item B<Outdenting Keywords>
You will probably also want to use the flag B<-skp> (previous item) too.
-The reason this is not recommended is that spacing a function paren can make a
+The parameter is not recommended because spacing a function paren can make a
program vulnerable to parsing problems by Perl. For example, the following
two-line program will run as written but will have a syntax error if
reformatted with -sfp:
=head2 Line Break Control
-The parameters in this section control breaks after
+The parameters in this and the next sections control breaks after
non-blank lines of code. Blank lines are controlled
separately by parameters in the section L<"Blank Line Control">.
=over 4
+=item B<-dnl>, B<--delete-old-newlines>
+
+By default, perltidy first deletes all old line break locations, and then it
+looks for good break points to match the desired line length. Use B<-ndnl>
+or B<--nodelete-old-newlines> to force perltidy to retain all old line break
+points.
+
+=item B<-anl>, B<--add-newlines>
+
+By default, perltidy will add line breaks when necessary to create
+continuations of long lines and to improve the script appearance. Use
+B<-nanl> or B<--noadd-newlines> to prevent any new line breaks.
+
+This flag does not prevent perltidy from eliminating existing line
+breaks; see B<--freeze-newlines> to completely prevent changes to line
+break points.
+
=item B<-fnl>, B<--freeze-newlines>
If you do not want any changes to the line breaks within
as they are, you can use the B<-fbl> flag which is described
in the section L<"Blank Line Control">.
+=back
+
+=head2 Controlling Breaks at Braces, Parens, and Square Brackets
+
+=over 4
+
=item B<-ce>, B<--cuddled-else>
Enable the "cuddled else" style, in which C<else> and C<elsif> are
When cuddled else formatting is selected with B<-ce>, setting this flag causes
perltidy to ignore its built-in defaults and rely exclusively on the block types
specified on the B<-cbl> flag described in the previous section. For example,
-to avoid using cuddled B<catch> and B<finally>, which among in the defaults, the
+to avoid using cuddled B<catch> and B<finally>, which are among the defaults, the
following set of parameters could be used:
perltidy -ce -cbl='else elsif continue' -cblx
-=item B<-cbo=n>, B<--cuddled-break-option=n>
+=item B<-cbo=n>, B<--cuddled-break-option=n>
Cuddled formatting is only possible between a pair of code blocks if the
closing brace of the first block starts a new line. If a block is encountered
-bbpi=1 outdent by one continuation level
-bbpi=2 indent one full indentation level
+=back
+
+=head2 Welding
+
+=over 4
+
=item B<-wn>, B<--weld-nested-containers>
The B<-wn> flag causes closely nested pairs of opening and closing container
sub declaration following an outer opening container symbol which is not a
code block brace, or (3) have an outer opening paren separated from the inner
opening symbol by any single non-container symbol or something that looks like
-a function evaluation, as illustrated in the next examples.
+a function evaluation, as illustrated in the next examples. An additional
+option (4) which can be turned on with the flag B<--weld-fat-comma> is when the opening container symbols are separated by a hash key and fat comma (=>).
Any container symbol may serve as both the inner container of one pair and as
the outer container of an adjacent pair. Consequently, any number of adjacent
Finally, the stacking of containers defined by this flag have priority over
any other container stacking flags. This is because any welding is done first.
+=item B<-wfc>, B<--weld-fat-comma >
+
+When the B<-wfc> flag is set, along with B<-wn>, perltidy is allowed to weld
+an opening paren to an inner opening container when they are separated by a hash key and fat comma (=>). for example
+
+ # perltidy -wn -wfc
+ elf->call_method( method_name_foo => {
+ some_arg1 => $foo,
+ some_other_arg3 => $bar->{'baz'},
+ } );
+
+This option is off by default.
+
=item B<-wnxl=s>, B<--weld-nested-exclusion-list>
The B<-wnxl=s> flag provides some control over the types of containers which
-wnxl='[ { q'
-means do B<NOT> include square-bracets, braces, or quotes in any welds. The only unspecified
+means do B<NOT> include square-brackets, braces, or quotes in any welds. The only unspecified
container is '(', so this string means that only welds involving parens will be made.
To illustrate, following welded snippet consists of a chain of three welded
'[ {' - exclude all brackets and braces
'[ ( ^K{' - exclude everything except nested structures like do {{ ... }}
+
=item B<Vertical tightness> of non-block curly braces, parentheses, and square brackets.
These parameters control what shall be called vertical tightness. Here are the
because it works on formatting globally rather than locally, as the B<-sot> and
B<-sct> flags do.
-=item B<-dnl>, B<--delete-old-newlines>
-
-By default, perltidy first deletes all old line break locations, and then it
-looks for good break points to match the desired line length. Use B<-ndnl>
-or B<--nodelete-old-newlines> to force perltidy to retain all old line break
-points.
-
-=item B<-anl>, B<--add-newlines>
-
-By default, perltidy will add line breaks when necessary to create
-continuations of long lines and to improve the script appearance. Use
-B<-nanl> or B<--noadd-newlines> to prevent any new line breaks.
-
-This flag does not prevent perltidy from eliminating existing line
-breaks; see B<--freeze-newlines> to completely prevent changes to line
-break points.
+=back
-=item B<Controlling whether perltidy breaks before or after operators>
+=head2 Breaking Before or After Operators
Four command line parameters provide some control over whether
a line break should be before or after specific token types.
except an B<=> one could use --bbao -wba='=' rather than listing every
single perl operator except B<=> on a -wbb flag.
-=item B<bal=n, --break-after-labels=n>
+=over 4
+
+=item B<-bal=n, --break-after-labels=n>
This flag controls whether or not a line break occurs after a label. There
are three possible values for B<n>:
=item B<-mft=n>, B<--maximum-fields-per-table=n>
-If the computed number of fields for any table exceeds B<n>, then it
-will be reduced to B<n>. The default value for B<n> is a large number,
-40. While this value should probably be left unchanged as a general
-rule, it might be used on a small section of code to force a list to
-have a particular number of fields per line, and then either the B<-boc>
-flag could be used to retain this formatting, or a single comment could
-be introduced somewhere to freeze the formatting in future applications
-of perltidy.
+If B<n> is a positive number, and the computed number of fields for any table
+exceeds B<n>, then it will be reduced to B<n>. This parameter might be used on
+a small section of code to force a list to have a particular number of fields
+per line, and then either the B<-boc> flag could be used to retain this
+formatting, or a single comment could be introduced somewhere to freeze the
+formatting in future applications of perltidy. For example
# perltidy -mft=2
@month_of_year = (
'Nov', 'Dec'
);
+The default value is B<n=0>, which does not place a limit on the
+number of fields in a table.
+
=item B<-cab=n>, B<--comma-arrow-breakpoints=n>
A comma which follows a comma arrow, '=>', is given special
=back
+=head2 Adding and Deleting Commas
+
+=over 4
+
+=item B<-drc>, B<--delete-repeated-commas>
+
+Repeated commas in a list are undesirable and can be removed with this flag.
+For example, given this list with a repeated comma
+
+ ignoreSpec( $file, "file",, \%spec, \%Rspec );
+
+we can remove it with -drc
+
+ # perltidy -drc:
+ ignoreSpec( $file, "file", \%spec, \%Rspec );
+
+Since the default is not to add or delete commas, this feature is off by default and must be requested.
+
+
+=item B<--want-trailing-commas=s> or B<-wtc=s>, B<--add-trailing-commas> or B<-atc>, and B<--delete-trailing-commas> or B<-dtc>
+
+A trailing comma is a comma following the last item of a list. Perl allows
+trailing commas but they are not required. By default, perltidy does not add
+or delete trailing commas, but it is possible to manipulate them with the
+following set of three related parameters:
+
+ --want-trailing-commas=s, -wtc=s - defines where trailing commas are wanted
+ --add-trailing-commas, -atc - gives permission to add trailing commas to match the style wanted
+ --delete-trailing-commas, -dtc - gives permission to delete trailing commas which do not match the style wanted
+
+The parameter B<--want-trailing-commas=s>, or B<-wtc=s>, defines a preferred style. The string B<s> indicates which lists should get trailing commas, as follows:
+
+ s=0 : no list should have a trailing comma
+ s=1 or * : every list should have a trailing comma
+ s=m a multi-line list should have a trailing commas
+ s=b trailing commas should be 'bare' (comma followed by newline)
+ s=h lists of key=>value pairs, with about one one '=>' and one ',' per line,
+ with a bare trailing comma
+ s=i lists with about one comma per line, with a bare trailing comma
+ s=' ' or -wtc not defined : leave trailing commas unchanged [DEFAULT].
+
+This parameter by itself only indicates the where trailing commas are
+wanted. Perltidy only adds these trailing commas if the flag B<--add-trailing-commas>, or B<-atc> is set. And perltidy only removes unwanted trailing commas
+if the flag B<--delete-trailing-commas>, or B<-dtc> is set.
+
+Here are some example parameter combinations and their meanings
+
+ -wtc=0 -dtc : delete all trailing commas
+ -wtc=1 -atc : all lists get trailing commas
+ -wtc=m -atc : all multi-line lists get trailing commas, but
+ single line lists remain unchanged.
+ -wtc=m -dtc : multi-line lists remain unchanged, but
+ any trailing commas on single line lists are removed.
+ -wtc=m -atc -dtc : all multi-line lists get trailing commas, and
+ any trailing commas on single line lists are removed.
+
+For example, given the following input without a trailing comma
+
+ bless {
+ B => $B,
+ Root => $Root
+ } => $package;
+
+we can add a trailing comma after the variable C<$Root> using
+
+ # perltidy -wtc=m -atc
+ bless {
+ B => $B,
+ Root => $Root,
+ } => $package;
+
+This could also be achieved in this case with B<-wtc=b> instead of B<-wtc=m>
+because the trailing comma here is bare (separated from its closing brace by a
+newline). And it could also be achieved with B<-wtc=h> because this particular
+list is a list of key=>value pairs.
+
+The above styles should cover the main of situations of interest, but it is
+possible to apply a different style to each type of container token by
+including an opening token ahead of the style character in the above table.
+For example
+
+ -wtc='(m [b'
+
+means that lists within parens should have multi-line trailing commas, and that
+lists within square brackets have bare trailing commas. Since there is no
+specification for curly braces in this example, their trailing commas would
+remain unchanged.
+
+For parentheses, an additional item of information which can be given is an
+alphanumeric letter which is used to limit the selection further depending on
+the type of token immediately before the opening paren. The possible letters
+are currently 'k', 'K', 'f', 'F', 'w', and 'W', with these meanings for
+matching whatever precedes an opening paren:
+
+ 'k' matches if the previous nonblank token is a perl built-in keyword (such as 'if', 'while'),
+ 'K' matches if 'k' does not, meaning that the previous token is not a keyword.
+ 'f' matches if the previous token is a function other than a keyword.
+ 'F' matches if 'f' does not.
+ 'w' matches if either 'k' or 'f' match.
+ 'W' matches if 'w' does not.
+
+These are the same codes used for B<--line-up-parentheses-inclusion-list>.
+For example,
+
+ -wtc = 'w(m'
+
+means that trailing commas are wanted for multi-line parenthesized lists following a function call or keyword.
+
+Here are some points to note regarding adding and deleting trailing commas:
+
+=over 4
+
+=item *
+
+For the implementation of these parameters, a B<list> is basically taken to be
+a container of items (parens, square brackets, or braces), which is not a code
+block, with one or more commas. These parameters only apply to something that
+fits this definition of a list.
+
+Note that a paren-less list of parameters is not a list by this definition, so
+these parameters have no effect on a peren-less list.
+
+Another consequence is that if the only comma in a list is deleted, then it
+cannot later be added back with these parameters because the container no
+longer fits this definition of a list. For example, given
+
+ my ( $self, ) = @_;
+
+and if we remove the comma with
+
+ # perltidy -wtc=m -dtc
+ my ( $self ) = @_;
+
+then we cannot use these trailing comma controls to add this comma back.
+
+=item *
+
+By B<multiline> list is meant a list for which the first comma and trailing comma
+are on different lines.
+
+=item *
+
+A B<bare> trailing comma is a comma which is at the end of a line. That is,
+the closing container token follows on a different line. So a list with a
+bare trailing comma is a special case of a multi-line list.
+
+=item *
+
+The decision regarding whether or not a list is multi-line or bare is
+made based on the B<input> stream. In some cases it may take an iteration
+or two to reach a final state.
+
+=item *
+
+When using these parameters for the first time it is a good idea to practice
+on some test scripts and verify that the results are as expected.
+
+=item *
+
+Since the default behavior is not to add or delete commas, these parameters
+can be useful on a temporary basis for reformatting a script.
+
+=back
+
+=item B<-dwic>, B<--delete-weld-interfering-commas>
+
+If the closing tokens of two nested containers are separated by a comma, then
+welding requested with B<--weld-nested-containers> cannot occur. Any commas in
+this situation are optional trailing commas and can be removed with B<-dwic>.
+For example, a comma in this script prevents welding:
+
+ # perltidy -wn
+ skip_symbols(
+ [ qw(
+ Perl_dump_fds
+ Perl_ErrorNo
+ Perl_GetVars
+ PL_sys_intern
+ ) ],
+ );
+
+Using B<-dwic> removes the comma and allows welding:
+
+ # perltidy -wn -dwic
+ skip_symbols( [ qw(
+ Perl_dump_fds
+ Perl_ErrorNo
+ Perl_GetVars
+ PL_sys_intern
+ ) ] );
+
+Since the default is not to add or delete commas, this feature is off by default.
+Here are some points to note about the B<-dwic> parameter
+
+=over 4
+
+=item *
+
+This operation is not reversible, so please check results of using this parameter carefully.
+
+=item *
+
+Removing this type of isolated trailing comma is necessary for welding to be
+possible, but not sufficient. So welding will not always occur where these
+commas are removed.
+
+=back
+
+=back
+
=head2 Retaining or Ignoring Existing Line Breaks
Several additional parameters are available for controlling the extent
By default, a method call arrow C<-E<gt>> is considered a candidate for
a breakpoint, but method chains will fill to the line width before a break is
considered. With B<-bom>, breaks before the arrow are preserved, so if you
-have preformatted a method chain:
+have pre-formatted a method chain:
my $q = $rs
->related_resultset('CDs')
Also note that the value of continuation indentation, -ci=4, is equal to the
value of the full indentation, -i=4. It is recommended that the either (1) the
-parameter B<-ci=2> be used instead, or the flag B<-xci> be set. This will help
-show structure, particularly when there are ternary statements. The following
-snippet illustrates these options.
+parameter B<-ci=2> be used instead, or (2) the flag B<-xci> be set. This will
+help show structure, particularly when there are ternary statements. The
+following snippet illustrates these options.
# perltidy -pbp
$self->{_text} = (
The B<-xci> flag was developed after the B<-pbp> parameters were published so you need
to include it separately.
-=item B<One-line blocks>
+=back
+
+=head2 One-Line Blocks
-There are a few points to note regarding one-line blocks. A one-line
-block is something like this,
+A one-line block is a block of code where the contents within the curly braces
+is short enough to fit on a single line. For example,
if ( -e $file ) { print "'$file' exists\n" }
-where the contents within the curly braces is short enough to fit
-on a single line.
+The alternative, a block which spans multiple lines, is said to be a broken
+block. With few exceptions, perltidy retains existing one-line blocks, if it
+is possible within the line-length constraint, but it does not attempt to form
+new ones. In other words, perltidy will try to follow the input file regarding
+broken and unbroken blocks.
-With few exceptions, perltidy retains existing one-line blocks, if it
-is possible within the line-length constraint, but it does not attempt
-to form new ones. In other words, perltidy will try to follow the
-one-line block style of the input file.
+The main exception to this rule is that perltidy will attempt to form new
+one-line blocks following the keywords C<map>, C<eval>, and C<sort>, C<eval>,
+because these code blocks are often small and most clearly displayed in a
+single line. This behavior can be controlled with the flag
+B<--one-line-block-exclusion-list> described below.
-If an existing one-line block is longer than the maximum line length,
-however, it will be broken into multiple lines. When this happens, perltidy
-checks for and adds any optional terminating semicolon (unless the B<-nasc>
-option is used) if the block is a code block.
+When the B<cuddled-else> style is used, the default treatment of one-line blocks
+may interfere with the cuddled style. In this case, the default behavior may
+be changed with the flag B<--cuddled-break-option=n> described elsehwere.
-The main exception is that perltidy will attempt to form new one-line
-blocks following the keywords C<map>, C<eval>, and C<sort>, because
-these code blocks are often small and most clearly displayed in a single
-line.
+When an existing one-line block is longer than the maximum line length, and
+must therefore be broken into multiple lines, perltidy checks for and adds any
+optional terminating semicolon (unless the B<-nasc> option is used) if the
+block is a code block.
-One-line block rules can conflict with the cuddled-else option. When
-the cuddled-else option is used, perltidy retains existing one-line
-blocks, even if they do not obey cuddled-else formatting.
+=over 4
-Occasionally, when one-line blocks get broken because they exceed the
-available line length, the formatting will violate the requested brace style.
-If this happens, reformatting the script a second time should correct
-the problem.
+=item B<-olbxl=s>, B<--one-line-block-exclusion-list=s>
-Sometimes it might be desirable to convert a script to have one-line blocks
-whenever possible. Although there is currently no flag for this, a simple
-workaround is to execute perltidy twice, once with the flag B<-noadd-newlines>
-and then once again with normal parameters, like this:
+As noted above, perltidy will, by default, attempt to create new one-line
+blocks for certain block types. This flag allows the user to prevent this behavior for the block types listed in the string B<s>. The list B<s> may
+include any of the words C<sort>, C<map>, C<grep>, C<eval>, or it may be C<*>
+to indicate all of these.
- cat infile | perltidy -nanl | perltidy >outfile
+So for example to prevent multi-line B<eval> blocks from becoming one-line
+blocks, the command would be B<-olbxl='eval'>. In this case, existing one-line B<eval> blocks will remain on one-line if possible, and existing multi-line
+B<eval> blocks will remain multi-line blocks.
-When executed on this snippet
+=item B<-olbn=n>, B<--one-line-block-nesting=n>
- if ( $? == -1 ) {
- die "failed to execute: $!\n";
- }
- if ( $? == -1 ) {
- print "Had enough.\n";
- die "failed to execute: $!\n";
- }
+Nested one-line blocks are lines with code blocks which themselves contain code
+blocks. For example, the following line is a nested one-line block.
-the result is
+ foreach (@list) { if ($_ eq $asked_for) { last } ++$found }
- if ( $? == -1 ) { die "failed to execute: $!\n"; }
- if ( $? == -1 ) {
- print "Had enough.\n";
- die "failed to execute: $!\n";
+The default behavior is to break such lines into multiple lines, but this
+behavior can be controlled with this flag. The values of n are:
+
+ n=0 break nested one-line blocks into multiple lines [DEFAULT]
+ n=1 stable: keep existing nested-one line blocks intact
+
+For the above example, the default formatting (B<-olbn=0>) is
+
+ foreach (@list) {
+ if ( $_ eq $asked_for ) { last }
+ ++$found;
}
-This shows that blocks with a single statement become one-line blocks.
+If the parameter B<-olbn=1> is given, then the line will be left intact if it
+is a single line in the source, or it will be broken into multiple lines if it
+is broken in multiple lines in the source.
=item B<-olbs=n>, B<--one-line-block-semicolons=n>
ending semicolons which terminate one-line blocks containing just one
semicolon. So these two options are not exact inverses.
-=item B<-olbn=n>, B<--one-line-block-nesting=n>
+=item B<Forming new one-line blocks>
-Nested one-line blocks are lines with code blocks which themselves contain code
-blocks. For example, the following line is a nested one-line block.
+Sometimes it might be desirable to convert a script to have one-line blocks
+whenever possible. Although there is currently no flag for this, a simple
+workaround is to execute perltidy twice, once with the flag B<-noadd-newlines>
+and then once again with normal parameters, like this:
- foreach (@list) { if ($_ eq $asked_for) { last } ++$found }
+ cat infile | perltidy -nanl | perltidy >outfile
-The default behavior is to break such lines into multiple lines, but this
-behavior can be controlled with this flag. The values of n are:
+When executed on this snippet
- n=0 break nested one-line blocks into multiple lines [DEFAULT]
- n=1 stable: keep existing nested-one line blocks intact
+ if ( $? == -1 ) {
+ die "failed to execute: $!\n";
+ }
+ if ( $? == -1 ) {
+ print "Had enough.\n";
+ die "failed to execute: $!\n";
+ }
-For the above example, the default formatting (B<-olbn=0>) is
+the result is
- foreach (@list) {
- if ( $_ eq $asked_for ) { last }
- ++$found;
+ if ( $? == -1 ) { die "failed to execute: $!\n"; }
+ if ( $? == -1 ) {
+ print "Had enough.\n";
+ die "failed to execute: $!\n";
}
-If the parameter B<-olbn=1> is given, then the line will be left intact if it
-is a single line in the source, or it will be broken into multiple lines if it
-is broken in multiple lines in the source.
+This shows that blocks with a single statement become one-line blocks.
+=item B<Breaking existing one-line blocks>
-=back
+There is no automatic way to break existing long one-line blocks into multiple
+lines, but this can be accomplished by processing a script, or section of a
+script, with a short value of the parameter B<maximum-line-length=n>. Then,
+when the script is reformatted again with the normal parameters, the blocks
+which were broken will remain broken (with the exceptions noted above).
+Another trick for doing this for certain block types is to format one time with
+the B<-cuddled-else> flag and B<--cuddled-break-option=2>. Then format again
+with the normal parameters. This will break any one-line blocks which are
+involved in a cuddled-else style.
+
+=back
=head2 Controlling Vertical Alignment
=back
+=head2 Extended Syntax
+
+This section describes some parameters for dealing with extended syntax.
+
+For another method of handling extended syntax see the section L<"Skipping Selected Sections of Code">.
+
+Also note that the module F<Perl::Tidy> supplies a pre-filter and post-filter capability. This requires calling the module from a separate program rather than through the binary F<perltidy>.
+
+=over 4
+
+=item B<-xs>, B<--extended-syntax>
+
+This flag allows perltidy to handle certain common extensions
+to the standard syntax without complaint.
+
+For example, without this flag a structure such as the following would generate
+a syntax error:
+
+ Method deposit( Num $amount) {
+ $self->balance( $self->balance + $amount );
+ }
+
+This flag is enabled by default but it can be deactivated with B<-nxs>.
+Probably the only reason to deactivate this flag is to generate more diagnostic
+messages when debugging a script.
+
+=item B<-sal=s>, B<--sub-alias-list=s>
+
+This flag causes one or more words to be treated the same as if they were the keyword B<sub>. The string B<s> contains one or more alias words, separated by spaces or commas.
+
+For example,
+
+ perltidy -sal='method fun _sub M4'
+
+will cause the perltidy to treat the words 'method', 'fun', '_sub' and 'M4' the same as if they were 'sub'. Note that if the alias words are separated by spaces then the string of words should be placed in quotes.
+
+Note that several other parameters accept a list of keywords, including 'sub' (see L<"Specifying Block Types">).
+You do not need to include any sub aliases in these lists. Just include keyword 'sub' if you wish, and all aliases are automatically included.
+
+=item B<-gal=s>, B<--grep-alias-list=s>
+
+This flag allows a code block following an external 'list operator' function to be formatted as if it followed one of the built-in keywords B<grep>, B<map> or B<sort>. The string B<s> contains the names of one or more such list operators, separated by spaces or commas.
+
+By 'list operator' is meant a function which is invoked in the form
+
+ word {BLOCK} @list
+
+Perltidy tries to keep code blocks for these functions intact, since they are usually short, and does not automatically break after the closing brace since a list may follow. It also does some special handling of continuation indentation.
+
+For example, the code block arguments to functions 'My_grep' and 'My_map' can be given formatting like 'grep' with
+
+ perltidy -gal='My_grep My_map'
+
+By default, the following list operators in List::Util are automatically included:
+
+ all any first none notall reduce reductions
+
+Any operators specified with B<--grep-alias-list> are added to this list.
+The next parameter can be used to remove words from this default list.
+
+=item B<-gaxl=s>, B<--grep-alias-exclusion-list=s>
+
+The B<-gaxl=s> flag provides a method for removing any of the default list operators given above
+by listing them in the string B<s>. To remove all of the default operators use B<-gaxl='*'>.
+
+=item B<-uf=s>, B<--use-feature=s>
+
+This flag tells perltidy to allow the syntax associated a pragma in string
+B<s>. Currently only the recognized values for the string are B<s='class'> or
+string B<s=' '>. The default is B<--use-feature='class'>. This enables
+perltidy to recognized the special words B<class>, B<method>, B<field>, and
+B<ADJUST>. If this causes a conflict with other uses of these words, the
+default can be turned off with B<--use-feature=' '>.
+
+=back
+
=head2 Other Controls
=over 4
B<-DEBUG> will write a file with extension F<.DEBUG> for each input file
showing the tokenization of all lines of code.
+=item B<Making a table of information on code blocks>
+
+A table listing information about the blocks of code in a file can be made with
+B<--dump-block-summary>, or B<-dbs>. This causes perltidy to read and parse
+the file, write a table of comma-separated values for selected code blocks to
+the standard output, and then exit. This parameter must be on the command
+line, not in a F<.perlticyrc> file, and it requires a single file name on the
+command line. For example
+
+ perltidy -dbs somefile.pl >blocks.csv
+
+produces an output file F<blocks.csv> whose lines hold these
+parameters:
+
+ filename - the name of the file
+ line - the line number of the opening brace of this block
+ line_count - the number of lines between opening and closing braces
+ code_lines - the number of lines excluding blanks, comments, and pod
+ type - the block type (sub, for, foreach, ...)
+ name - the block name if applicable (sub name, label, asub name)
+ depth - the nesting depth of the opening block brace
+ max_change - the change in depth to the most deeply nested code block
+ block_count - the total number of code blocks nested in this block
+ mccabe_count - the McCabe complexity measure of this code block
+
+This feature was developed to help identify complex sections of code as an aid
+in refactoring. The McCabe complexity measure follows the definition used by
+Perl::Critic. By default the table contains these values for subroutines, but
+the user may request them for any or all blocks of code or packages. For
+blocks which are loops nested within loops, a postfix '+' to the C<type> is
+added to indicate possible code complexity. Although the table does not
+otherwise indicate which blocks are nested in other blocks, this can be
+determined by computing and comparing the block ending line numbers.
+
+By default the table lists subroutines with more than 20 C<code_lines>, but
+this can be changed with the following two parameters:
+
+B<--dump-block-minimum-lines=n>, or B<-dbl=n>, where B<n> is the minimum
+number of C<code_lines> to be included. The default is B<-n=20>. Note that
+C<code_lines> is the number of lines excluding and comments, blanks and pod.
+
+B<--dump-block-types=s>, or B<-dbt=s>, where string B<s> is a list of block
+types to be included. The type of a block is either the name of the perl
+builtin keyword for that block (such as B<sub if elsif else for foreach ..>) or
+the word immediately before the opening brace. In addition, there are
+a few symbols for special block types, as follows:
+
+ if elsif else for foreach ... any keyword introducing a block
+ sub - any sub or anynomous sub
+ asub - any anonymous sub
+ * - any block except nameless blocks
+ + - any nested inner block loop
+ package - any package or class
+ closure - any nameless block
+
+In addition, specific block loop types which are nested in other loops can be
+selected by adding a B<+> after the block name. (Nested loops are sometimes
+good candidates for restructuring).
+
+The default is B<-dbt='sub'>.
+
+In the following examples a table C<block.csv> is created for a file
+C<somefile.pl>:
+
+=over 4
+
+=item *
+This selects both C<subs> and C<packages> which have 20 or more lines of code.
+This can be useful in code which contains multiple packages.
+
+ perltidy -dbs -dbt='sub package' somefile.pl >blocks.csv
+
+=item *
+This selects block types C<sub for foreach while> with 10 or more code lines.
+
+ perltidy -dbs -dbl=10 -dbt='sub for foreach while' somefile.pl >blocks.csv
+
+=item *
+This selects blocks with 2 or more code lines which are type C<sub> or which
+are inner loops.
+
+ perltidy -dbs -dbl=2 -dbt='sub +' somefile.pl >blocks.csv
+
+=item *
+This selects every block and package.
+
+ perltidy -dbs -dbl=1 -dbt='* closure' somefile.pl >blocks.csv
+
+=back
+
+
=item B<Working with MakeMaker, AutoLoader and SelfLoader>
The first $VERSION line of a file which might be eval'd by MakeMaker
The following list shows all short parameter names which allow a prefix
'n' to produce the negated form:
- D anl asbl asc ast asu atnl aws b baa
- baao bar bbao bbb bbc bbs bl bli boa boc
- bok bol bom bos bot cblx ce conv cs csc
- cscb cscw dac dbc dcbl dcsc ddf dln dnl dop
- dp dpro dsc dsm dsn dtt dwls dwrs dws eos
- f fll fpva frm fs fso gcs hbc hbcm hbco
- hbh hbhh hbi hbj hbk hbm hbn hbp hbpd hbpu
- hbq hbs hbsc hbv hbw hent hic hicm hico hih
- hihh hii hij hik him hin hip hipd hipu hiq
- his hisc hiv hiw hsc html ibc icb icp iob
- isbc iscl kgb kgbd kgbi kis lal log lop lp
- lsl mem nib ohbr okw ola olc oll olq opr
- opt osbc osbr otr ple pod pvl q sac sbc
- sbl scbb schb scp scsb sct se sfp sfs skp
- sob sobb sohb sop sosb sot ssc st sts t
- tac tbc toc tp tqw trp ts tsc tso vbc
- vc vmll vsc w wn x xci xlp xs
+ D anl asbl asc ast asu atc atnl aws b
+ baa baao bar bbao bbb bbc bbs bl bli boa
+ boc bok bol bom bos bot cblx ce conv cpb
+ cs csc cscb cscw dac dbc dbs dcbl dcsc ddf
+ dln dnl dop dp dpro drc dsc dsm dsn dtc
+ dtt dwic dwls dwrs dws eos f fll fpva frm
+ fs fso gcs hbc hbcm hbco hbh hbhh hbi hbj
+ hbk hbm hbn hbp hbpd hbpu hbq hbs hbsc hbv
+ hbw hent hic hicm hico hih hihh hii hij hik
+ him hin hip hipd hipu hiq his hisc hiv hiw
+ hsc html ibc icb icp iob isbc iscl kgb kgbd
+ kgbi kis lal log lop lp lsl mem nib ohbr
+ okw ola olc oll olq opr opt osbc osbr otr
+ ple pod pvl q sac sbc sbl scbb schb scp
+ scsb sct se sfp sfs skp sob sobb sohb sop
+ sosb sot ssc st sts t tac tbc toc tp
+ tqw trp ts tsc tso vbc vc vmll vsc w
+ wfc wn x xci xlp xs
Equivalently, the prefix 'no' or 'no-' on the corresponding long names may be
used.
=head1 VERSION
-This man page documents perltidy version 20220613
+This man page documents perltidy version 20230309
=head1 BUG REPORTS
projects / perltidy.git / blobdiff