Regular Expressions 101

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An explanation of your regex will be automatically generated as you type.
Detailed match information will be displayed here automatically.
  • All Tokens
  • Common Tokens
  • General Tokens
  • Anchors
  • Meta Sequences
  • Quantifiers
  • Group Constructs
  • Character Classes
  • Flags/Modifiers
  • Substitution
  • A single character of: a, b or c
    [abc]
  • A character except: a, b or c
    [^abc]
  • A character in the range: a-z
    [a-z]
  • A character not in the range: a-z
    [^a-z]
  • A character in the range: a-z or A-Z
    [a-zA-Z]
  • Any single character
    .
  • Alternate - match either a or b
    a|b
  • Any whitespace character
    \s
  • Any non-whitespace character
    \S
  • Any digit
    \d
  • Any non-digit
    \D
  • Any word character
    \w
  • Any non-word character
    \W
  • Non-capturing group
    (?:...)
  • Capturing group
    (...)
  • Zero or one of a
    a?
  • Zero or more of a
    a*
  • One or more of a
    a+
  • Exactly 3 of a
    a{3}
  • 3 or more of a
    a{3,}
  • Between 3 and 6 of a
    a{3,6}
  • Start of string
    ^
  • End of string
    $
  • A word boundary
    \b
  • Non-word boundary
    \B

Regular Expression
No Match

/
/
gm

Test String

Code Generator

Language

Generated Code

use strict; my $str = '000 001 002 003 004 005 006 007 010 011 012 013 014 015 016 017 020 021 022 023 024 025 026 027 030 031 032 033 034 035 036 037 040 041 042 043 044 045 046 047 050 051 052 053 054 055 056 057 060 061 062 063 064 065 066 067 070 071 072 073 074 075 076 077 100 101 102 103 104 105 106 107 110 111 112 113 114 115 116 117 120 121 122 123 124 125 126 127 130 131 132 133 134 135 136 137 140 141 142 143 144 145 146 147 150 151 152 153 154 155 156 157 160 161 162 163 164 165 166 167 170 171 172 173 174 175 176 177 200 201 202 203 204 205 206 207 210 211 212 213 214 215 216 217 220 221 222 223 224 225 226 227 230 231 232 233 234 235 236 237 240 241 242 243 244 245 246 247 250 251 252 253 254 255 256 257 260 261 262 263 264 265 266 267 270 271 272 273 274 275 276 277 300 301 302 303 304 305 306 307 310 311 312 313 314 315 316 317 320 321 322 323 324 325 326 327 330 331 332 333 334 335 336 337 340 341 342 343 344 345 346 347 350 351 352 353 354 355 356 357 360 361 362 363 364 365 366 367 370 371 372 373 374 375 376 377 400 401 402 403 404 405 406 407 410 411 412 413 414 415 416 417 420 421 422 423 424 425 426 427 430 431 432 433 434 435 436 437 440 441 442 443 444 445 446 447 450 451 452 453 454 455 456 457 460 461 462 463 464 465 466 467 470 471 472 473 474 475 476 477 500 501 502 503 504 505 506 507 510 511 512 513 514 515 516 517 520 521 522 523 524 525 526 527 530 531 532 533 534 535 536 537 540 541 542 543 544 545 546 547 550 551 552 553 554 555 556 557 560 561 562 563 564 565 566 567 570 571 572 573 574 575 576 577 600 601 602 603 604 605 606 607 610 611 612 613 614 615 616 617 620 621 622 623 624 625 626 627 630 631 632 633 634 635 636 637 640 641 642 643 644 645 646 647 650 651 652 653 654 655 656 657 660 661 662 663 664 665 666 667 670 671 672 673 674 675 676 677 700 701 702 703 704 705 706 707 710 711 712 713 714 715 716 717 720 721 722 723 724 725 726 727 730 731 732 733 734 735 736 737 740 741 742 743 744 745 746 747 750 751 752 753 754 755 756 757 760 761 762 763 764 765 766 767 770 771 772 773 774 775 776 777'; my $regex = qr/[0-7]{3}/mp; if ( $str =~ /$regex/g ) { print "Whole match is ${^MATCH} and its start/end positions can be obtained via \$-[0] and \$+[0]\n"; # print "Capture Group 1 is $1 and its start/end positions can be obtained via \$-[1] and \$+[1]\n"; # print "Capture Group 2 is $2 ... and so on\n"; } # ${^POSTMATCH} and ${^PREMATCH} are also available with the use of '/p' # Named capture groups can be called via $+{name}

Please keep in mind that these code samples are automatically generated and are not guaranteed to work. If you find any syntax errors, feel free to submit a bug report. For a full regex reference for Perl, please visit: http://perldoc.perl.org/perlre.html