file compiled by Perl. The same is also true for C<eval>ed strings
that contain subroutines, or which are currently being executed.
The $filename for C<eval>ed strings looks like C<(eval 34)>.
-Code assertions in regexes look like C<(re_eval 19)>.
Values in this array are magical in numeric context: they compare
equal to zero only if the line is not breakable.
The same holds for evaluated strings that contain subroutines, or
which are currently being executed. The $filename for C<eval>ed strings
-looks like C<(eval 34)> or C<(re_eval 19)>.
+looks like C<(eval 34)>.
=item *
Each scalar C<${"_<$filename"}> contains C<"_<$filename">. This is
also the case for evaluated strings that contain subroutines, or
which are currently being executed. The $filename for C<eval>ed
-strings looks like C<(eval 34)> or C<(re_eval 19)>.
+strings looks like C<(eval 34)>.
=item *
A hash C<%DB::sub> is maintained, whose keys are subroutine names
and whose values have the form C<filename:startline-endline>.
C<filename> has the form C<(eval 34)> for subroutines defined inside
-C<eval>s, or C<(re_eval 19)> for those within regex code assertions.
+C<eval>s.
=item *
After the rc file is read, the debugger reads the PERLDB_OPTS
environment variable and uses it to set debugger options. The
contents of this variable are treated as if they were the argument
-of an C<o ...> debugger command (q.v. in L<perldebug/Options>).
+of an C<o ...> debugger command (q.v. in L<perldebug/"Configurable Options">).
=head3 Debugger Internal Variables
Loading DB routines from perl5db.pl patch level 0.94
Emacs support available.
- Enter h or `h h' for help.
+ Enter h or 'h h' for help.
main::(-e:1): 0
DB<1> sub foo { 14 }
The debugging output at compile time looks like this:
- Compiling REx `[bc]d(ef*g)+h[ij]k$'
+ Compiling REx '[bc]d(ef*g)+h[ij]k$'
size 45 Got 364 bytes for offset annotations.
first at 1
rarest char g at 0
42: EXACT <k>(44)
44: EOL(45)
45: END(0)
- anchored `de' at 1 floating `gh' at 3..2147483647 (checking floating)
- stclass `ANYOF[bc]' minlen 7
+ anchored 'de' at 1 floating 'gh' at 3..2147483647 (checking floating)
+ stclass 'ANYOF[bc]' minlen 7
Offsets: [45]
1[4] 0[0] 0[0] 0[0] 0[0] 0[0] 0[0] 0[0] 0[0] 0[0] 0[0] 5[1]
0[0] 12[1] 0[0] 6[1] 0[0] 7[1] 0[0] 9[1] 8[1] 0[0] 10[1] 0[0]
The
- anchored `de' at 1 floating `gh' at 3..2147483647 (checking floating)
- stclass `ANYOF[bc]' minlen 7
+ anchored 'de' at 1 floating 'gh' at 3..2147483647 (checking floating)
+ stclass 'ANYOF[bc]' minlen 7
line (split into two lines above) contains optimizer
information. In the example shown, the optimizer found that the match
=back
If a substring is known to match at end-of-line only, it may be
-followed by C<$>, as in C<floating `k'$>.
+followed by C<$>, as in C<floating 'k'$>.
The optimizer-specific information is used to avoid entering (a slow) regex
engine on strings that will not definitely match. If the C<isall> flag
Here are the possible types, with short descriptions:
- # TYPE arg-description [num-args] [longjump-len] DESCRIPTION
-
- # Exit points
- END no End of program.
- SUCCEED no Return from a subroutine, basically.
-
- # Anchors:
- BOL no Match "" at beginning of line.
- MBOL no Same, assuming multiline.
- SBOL no Same, assuming singleline.
- EOS no Match "" at end of string.
- EOL no Match "" at end of line.
- MEOL no Same, assuming multiline.
- SEOL no Same, assuming singleline.
- BOUND no Match "" at any word boundary
- BOUNDL no Match "" at any word boundary
- NBOUND no Match "" at any word non-boundary
- NBOUNDL no Match "" at any word non-boundary
- GPOS no Matches where last m//g left off.
-
- # [Special] alternatives
- ANY no Match any one character (except newline).
- SANY no Match any one character.
- ANYOF sv Match character in (or not in) this class.
- ALNUM no Match any alphanumeric character
- ALNUML no Match any alphanumeric char in locale
- NALNUM no Match any non-alphanumeric character
- NALNUML no Match any non-alphanumeric char in locale
- SPACE no Match any whitespace character
- SPACEL no Match any whitespace char in locale
- NSPACE no Match any non-whitespace character
- NSPACEL no Match any non-whitespace char in locale
- DIGIT no Match any numeric character
- NDIGIT no Match any non-numeric character
-
- # BRANCH The set of branches constituting a single choice are hooked
- # together with their "next" pointers, since precedence prevents
- # anything being concatenated to any individual branch. The
- # "next" pointer of the last BRANCH in a choice points to the
- # thing following the whole choice. This is also where the
- # final "next" pointer of each individual branch points; each
- # branch starts with the operand node of a BRANCH node.
- #
- BRANCH node Match this alternative, or the next...
-
- # BACK Normal "next" pointers all implicitly point forward; BACK
- # exists to make loop structures possible.
- # not used
- BACK no Match "", "next" ptr points backward.
-
- # Literals
- EXACT sv Match this string (preceded by length).
- EXACTF sv Match this string, folded (prec. by length).
- EXACTFL sv Match this string, folded in locale (w/len).
-
- # Do nothing
- NOTHING no Match empty string.
- # A variant of above which delimits a group, thus stops optimizations
- TAIL no Match empty string. Can jump here from outside.
-
- # STAR,PLUS '?', and complex '*' and '+', are implemented as circular
- # BRANCH structures using BACK. Simple cases (one character
- # per match) are implemented with STAR and PLUS for speed
- # and to minimize recursive plunges.
- #
- STAR node Match this (simple) thing 0 or more times.
- PLUS node Match this (simple) thing 1 or more times.
-
- CURLY sv 2 Match this simple thing {n,m} times.
- CURLYN no 2 Match next-after-this simple thing
- # {n,m} times, set parens.
- CURLYM no 2 Match this medium-complex thing {n,m} times.
- CURLYX sv 2 Match this complex thing {n,m} times.
-
- # This terminator creates a loop structure for CURLYX
- WHILEM no Do curly processing and see if rest matches.
-
- # OPEN,CLOSE,GROUPP ...are numbered at compile time.
- OPEN num 1 Mark this point in input as start of #n.
- CLOSE num 1 Analogous to OPEN.
-
- REF num 1 Match some already matched string
- REFF num 1 Match already matched string, folded
- REFFL num 1 Match already matched string, folded in loc.
-
- # grouping assertions
- IFMATCH off 1 2 Succeeds if the following matches.
- UNLESSM off 1 2 Fails if the following matches.
- SUSPEND off 1 1 "Independent" sub-regex.
- IFTHEN off 1 1 Switch, should be preceded by switcher.
- GROUPP num 1 Whether the group matched.
-
- # Support for long regex
- LONGJMP off 1 1 Jump far away.
- BRANCHJ off 1 1 BRANCH with long offset.
-
- # The heavy worker
- EVAL evl 1 Execute some Perl code.
-
- # Modifiers
- MINMOD no Next operator is not greedy.
- LOGICAL no Next opcode should set the flag only.
-
- # This is not used yet
- RENUM off 1 1 Group with independently numbered parens.
-
- # This is not really a node, but an optimized-away piece of a "long" node.
- # To simplify debugging output, we mark it as if it were a node
- OPTIMIZED off Placeholder for dump.
+ # TYPE arg-description [num-args] [longjump-len] DESCRIPTION
+
+ # Exit points
+ END no End of program.
+ SUCCEED no Return from a subroutine, basically.
+
+ # Anchors:
+
+ BOL no Match "" at beginning of line.
+ MBOL no Same, assuming multiline.
+ SBOL no Same, assuming singleline.
+ EOS no Match "" at end of string.
+ EOL no Match "" at end of line.
+ MEOL no Same, assuming multiline.
+ SEOL no Same, assuming singleline.
+ BOUND no Match "" at any word boundary using native charset
+ semantics for non-utf8
+ BOUNDL no Match "" at any locale word boundary
+ BOUNDU no Match "" at any word boundary using Unicode semantics
+ BOUNDA no Match "" at any word boundary using ASCII semantics
+ NBOUND no Match "" at any word non-boundary using native charset
+ semantics for non-utf8
+ NBOUNDL no Match "" at any locale word non-boundary
+ NBOUNDU no Match "" at any word non-boundary using Unicode semantics
+ NBOUNDA no Match "" at any word non-boundary using ASCII semantics
+ GPOS no Matches where last m//g left off.
+
+ # [Special] alternatives:
+
+ REG_ANY no Match any one character (except newline).
+ SANY no Match any one character.
+ CANY no Match any one byte.
+ ANYOF sv Match character in (or not in) this class, single char
+ match only
+ ANYOFV sv Match character in (or not in) this class, can
+ match-multiple chars
+ ALNUM no Match any alphanumeric character using native charset
+ semantics for non-utf8
+ ALNUML no Match any alphanumeric char in locale
+ ALNUMU no Match any alphanumeric char using Unicode semantics
+ ALNUMA no Match [A-Za-z_0-9]
+ NALNUM no Match any non-alphanumeric character using native charset
+ semantics for non-utf8
+ NALNUML no Match any non-alphanumeric char in locale
+ NALNUMU no Match any non-alphanumeric char using Unicode semantics
+ NALNUMA no Match [^A-Za-z_0-9]
+ SPACE no Match any whitespace character using native charset
+ semantics for non-utf8
+ SPACEL no Match any whitespace char in locale
+ SPACEU no Match any whitespace char using Unicode semantics
+ SPACEA no Match [ \t\n\f\r]
+ NSPACE no Match any non-whitespace character using native charset
+ semantics for non-utf8
+ NSPACEL no Match any non-whitespace char in locale
+ NSPACEU no Match any non-whitespace char using Unicode semantics
+ NSPACEA no Match [^ \t\n\f\r]
+ DIGIT no Match any numeric character using native charset semantics
+ for non-utf8
+ DIGITL no Match any numeric character in locale
+ DIGITA no Match [0-9]
+ NDIGIT no Match any non-numeric character using native charset
+ i semantics for non-utf8
+ NDIGITL no Match any non-numeric character in locale
+ NDIGITA no Match [^0-9]
+ CLUMP no Match any extended grapheme cluster sequence
+
+ # Alternation
+
+ # BRANCH The set of branches constituting a single choice are hooked
+ # together with their "next" pointers, since precedence prevents
+ # anything being concatenated to any individual branch. The
+ # "next" pointer of the last BRANCH in a choice points to the
+ # thing following the whole choice. This is also where the
+ # final "next" pointer of each individual branch points; each
+ # branch starts with the operand node of a BRANCH node.
+ #
+ BRANCH node Match this alternative, or the next...
+
+ # Back pointer
+
+ # BACK Normal "next" pointers all implicitly point forward; BACK
+ # exists to make loop structures possible.
+ # not used
+ BACK no Match "", "next" ptr points backward.
+
+ # Literals
+
+ EXACT str Match this string (preceded by length).
+ EXACTF str Match this string, folded, native charset semantics for
+ non-utf8 (prec. by length).
+ EXACTFL str Match this string, folded in locale (w/len).
+ EXACTFU str Match this string, folded, Unicode semantics for non-utf8
+ (prec. by length).
+ EXACTFA str Match this string, folded, Unicode semantics for non-utf8,
+ but no ASCII-range character matches outside ASCII (prec.
+ by length),.
+
+ # Do nothing types
+
+ NOTHING no Match empty string.
+ # A variant of above which delimits a group, thus stops optimizations
+ TAIL no Match empty string. Can jump here from outside.
+
+ # Loops
+
+ # STAR,PLUS '?', and complex '*' and '+', are implemented as circular
+ # BRANCH structures using BACK. Simple cases (one character
+ # per match) are implemented with STAR and PLUS for speed
+ # and to minimize recursive plunges.
+ #
+ STAR node Match this (simple) thing 0 or more times.
+ PLUS node Match this (simple) thing 1 or more times.
+
+ CURLY sv 2 Match this simple thing {n,m} times.
+ CURLYN no 2 Capture next-after-this simple thing
+ CURLYM no 2 Capture this medium-complex thing {n,m} times.
+ CURLYX sv 2 Match this complex thing {n,m} times.
+
+ # This terminator creates a loop structure for CURLYX
+ WHILEM no Do curly processing and see if rest matches.
+
+ # Buffer related
+
+ # OPEN,CLOSE,GROUPP ...are numbered at compile time.
+ OPEN num 1 Mark this point in input as start of #n.
+ CLOSE num 1 Analogous to OPEN.
+
+ REF num 1 Match some already matched string
+ REFF num 1 Match already matched string, folded using native charset
+ semantics for non-utf8
+ REFFL num 1 Match already matched string, folded in loc.
+ REFFU num 1 Match already matched string, folded using unicode
+ semantics for non-utf8
+ REFFA num 1 Match already matched string, folded using unicode
+ semantics for non-utf8, no mixing ASCII, non-ASCII
+
+ # Named references. Code in regcomp.c assumes that these all are after the
+ # numbered references
+ NREF no-sv 1 Match some already matched string
+ NREFF no-sv 1 Match already matched string, folded using native charset
+ semantics for non-utf8
+ NREFFL no-sv 1 Match already matched string, folded in loc.
+ NREFFU num 1 Match already matched string, folded using unicode
+ semantics for non-utf8
+ NREFFA num 1 Match already matched string, folded using unicode
+ semantics for non-utf8, no mixing ASCII, non-ASCII
+
+ IFMATCH off 1 2 Succeeds if the following matches.
+ UNLESSM off 1 2 Fails if the following matches.
+ SUSPEND off 1 1 "Independent" sub-RE.
+ IFTHEN off 1 1 Switch, should be preceded by switcher.
+ GROUPP num 1 Whether the group matched.
+
+ # Support for long RE
+
+ LONGJMP off 1 1 Jump far away.
+ BRANCHJ off 1 1 BRANCH with long offset.
+
+ # The heavy worker
+
+ EVAL evl 1 Execute some Perl code.
+
+ # Modifiers
+
+ MINMOD no Next operator is not greedy.
+ LOGICAL no Next opcode should set the flag only.
+
+ # This is not used yet
+ RENUM off 1 1 Group with independently numbered parens.
+
+ # Trie Related
+
+ # Behave the same as A|LIST|OF|WORDS would. The '..C' variants have
+ # inline charclass data (ascii only), the 'C' store it in the structure.
+ # NOTE: the relative order of the TRIE-like regops is significant
+
+ TRIE trie 1 Match many EXACT(F[ALU]?)? at once. flags==type
+ TRIEC charclass Same as TRIE, but with embedded charclass data
+
+ # For start classes, contains an added fail table.
+ AHOCORASICK trie 1 Aho Corasick stclass. flags==type
+ AHOCORASICKC charclass Same as AHOCORASICK, but with embedded charclass data
+
+ # Regex Subroutines
+ GOSUB num/ofs 2L recurse to paren arg1 at (signed) ofs arg2
+ GOSTART no recurse to start of pattern
+
+ # Special conditionals
+ NGROUPP no-sv 1 Whether the group matched.
+ INSUBP num 1 Whether we are in a specific recurse.
+ DEFINEP none 1 Never execute directly.
+
+ # Backtracking Verbs
+ ENDLIKE none Used only for the type field of verbs
+ OPFAIL none Same as (?!)
+ ACCEPT parno 1 Accepts the current matched string.
+
+
+ # Verbs With Arguments
+ VERB no-sv 1 Used only for the type field of verbs
+ PRUNE no-sv 1 Pattern fails at this startpoint if no-backtracking through this
+ MARKPOINT no-sv 1 Push the current location for rollback by cut.
+ SKIP no-sv 1 On failure skip forward (to the mark) before retrying
+ COMMIT no-sv 1 Pattern fails outright if backtracking through this
+ CUTGROUP no-sv 1 On failure go to the next alternation in the group
+
+ # Control what to keep in $&.
+ KEEPS no $& begins here.
+
+ # New charclass like patterns
+ LNBREAK none generic newline pattern
+ VERTWS none vertical whitespace (Perl 6)
+ NVERTWS none not vertical whitespace (Perl 6)
+ HORIZWS none horizontal whitespace (Perl 6)
+ NHORIZWS none not horizontal whitespace (Perl 6)
+
+ FOLDCHAR codepoint 1 codepoint with tricky case folding properties.
+
+ # SPECIAL REGOPS
+
+ # This is not really a node, but an optimized away piece of a "long" node.
+ # To simplify debugging output, we mark it as if it were a node
+ OPTIMIZED off Placeholder for dump.
+
+ # Special opcode with the property that no opcode in a compiled program
+ # will ever be of this type. Thus it can be used as a flag value that
+ # no other opcode has been seen. END is used similarly, in that an END
+ # node cant be optimized. So END implies "unoptimizable" and PSEUDO mean
+ # "not seen anything to optimize yet".
+ PSEUDO off Pseudo opcode for internal use.
=for unprinted-credits
Next section M-J. Dominus (mjd-perl-patch+@plover.com) 20010421
If the regex engine was entered, the output may look like this:
- Matching `[bc]d(ef*g)+h[ij]k$' against `abcdefg__gh__'
+ Matching '[bc]d(ef*g)+h[ij]k$' against 'abcdefg__gh__'
Setting an EVAL scope, savestack=3
2 <ab> <cdefg__gh_> | 1: ANYOF
3 <abc> <defg__gh_> | 11: EXACT <d>
https://perl5.git.perl.org / perl5.git / blobdiff