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
Processing...

Test String

Code Generator

Generated Code

#include <StringConstants.au3> ; to declare the Constants of StringRegExp #include <Array.au3> ; UDF needed for _ArrayDisplay and _ArrayConcatenate Local $sRegex = "(?sm)^\s+(?:re)?start.*?(haproxy_check).*?;;" Local $sString = "case "$1" in" & @CRLF & _ " start)" & @CRLF & _ " echo -n "Starting haproxy "" & @CRLF & _ " ## Start daemon with startproc(8). If this fails" & @CRLF & _ " ## the return value is set appropriately by startproc." & @CRLF & _ " haproxy_check" & @CRLF & _ " /sbin/startproc $HAPROXY_BIN -D -f $HAPROXY_CONF -p $HAPROXY_PID" & @CRLF & _ " # Remember status and be verbose" & @CRLF & _ " rc_status -v" & @CRLF & _ " ;;" & @CRLF & _ " stop)" & @CRLF & _ " echo -n "Shutting down haproxy "" & @CRLF & _ " ## Stop daemon with killproc(8) and if this fails" & @CRLF & _ " ## killproc sets the return value according to LSB." & @CRLF & _ "" & @CRLF & _ " /sbin/killproc -TERM $HAPROXY_BIN" & @CRLF & _ "" & @CRLF & _ " # this is additional forcing kill command to ensure that all processes are stopped." & @CRLF & _ " /usr/bin/killall -9 $HAPROXY_BIN || true" & @CRLF & _ " # Remember status and be verbose" & @CRLF & _ " rc_status -v" & @CRLF & _ " ;;" & @CRLF & _ " try-restart|condrestart)" & @CRLF & _ " ## Do a restart only if the service was active before." & @CRLF & _ " ## Note: try-restart is now part of LSB (as of 1.9)." & @CRLF & _ " ## RH has a similar command named condrestart." & @CRLF & _ " if test "$1" = "condrestart"; then" & @CRLF & _ " echo "${attn} Use try-restart ${done}(LSB)${attn} rather than condrestart ${warn}(RH)${norm}"" & @CRLF & _ " fi" & @CRLF & _ " $0 status" & @CRLF & _ " if test $? = 0; then" & @CRLF & _ " # we us reload here for a graceful restart during update" & @CRLF & _ " $0 reload" & @CRLF & _ " else" & @CRLF & _ " rc_reset # Not running is not a failure." & @CRLF & _ " fi" & @CRLF & _ " # Remember status and be quiet" & @CRLF & _ " rc_status" & @CRLF & _ " ;;" & @CRLF & _ " restart)" & @CRLF & _ " ## Stop the service and regardless of whether it was" & @CRLF & _ " ## running or not, start it again." & @CRLF & _ " $0 stop" & @CRLF & _ " $0 start" & @CRLF & _ " haproxy_check" & @CRLF & _ " # Remember status and be quiet" & @CRLF & _ " rc_status" & @CRLF & _ " ;;" & @CRLF & _ " check)" & @CRLF & _ " ## Stop the service and regardless of whether it was" & @CRLF & _ " ## running or not, start it again." & @CRLF & _ " echo -n "Checking config of haproxy "" & @CRLF & _ " haproxy_check" & @CRLF & _ " rc_status -v" & @CRLF & _ " ;;" & @CRLF & _ " reload|force-reload)" & @CRLF & _ " ## Like force-reload, but if daemon does not support" & @CRLF & _ " ## signaling, do nothing (!)" & @CRLF & _ "" & @CRLF & _ " haproxy_check" & @CRLF & _ " # If it supports signaling:" & @CRLF & _ " echo -n "Reload service haproxy "" & @CRLF & _ " $HAPROXY_BIN -p $HAPROXY_PID -D -f $HAPROXY_CONF -sf $(cat $HAPROXY_PID)" & @CRLF & _ " rc_status -v" & @CRLF & _ " ;;" & @CRLF & _ " status)" & @CRLF & _ " echo -n "Checking for service haproxy "" & @CRLF & _ " ## Check status with checkproc(8), if process is running" & @CRLF & _ " ## checkproc will return with exit status 0." & @CRLF & _ "" & @CRLF & _ " # Return value is slightly different for the status command:" & @CRLF & _ " # 0 - service up and running" & @CRLF & _ " # 1 - service dead, but /var/run/ pid file exists" & @CRLF & _ " # 2 - service dead, but /var/lock/ lock file exists" & @CRLF & _ " # 3 - service not running (unused)" & @CRLF & _ " # 4 - service status unknown :-(" & @CRLF & _ " # 5--199 reserved (5--99 LSB, 100--149 distro, 150--199 appl.)" & @CRLF & _ "" & @CRLF & _ " # NOTE: checkproc returns LSB compliant status values." & @CRLF & _ " /sbin/checkproc $HAPROXY_BIN" & @CRLF & _ " # NOTE: rc_status knows that we called this init script with" & @CRLF & _ " # "status" option and adapts its messages accordingly." & @CRLF & _ " rc_status -v" & @CRLF & _ " ;;" & @CRLF & _ " probe)" & @CRLF & _ " ## Optional: Probe for the necessity of a reload, print out the" & @CRLF & _ " ## argument to this init script which is required for a reload." & @CRLF & _ " ## Note: probe is not (yet) part of LSB (as of 1.9)" & @CRLF & _ "" & @CRLF & _ " test $HAPROXY_CONF -nt $HAPROXY_PID && echo reload" & @CRLF & _ " ;;" & @CRLF & _ " *)" & @CRLF & _ " echo "Usage: $0 {start|stop|status|try-restart|restart|force-reload|reload|probe}"" & @CRLF & _ " exit 1" & @CRLF & _ " ;;" & @CRLF & _ "esac" Local $aArray = StringRegExp($sString, $sRegex, $STR_REGEXPARRAYGLOBALFULLMATCH) Local $aFullArray[0] For $i = 0 To UBound($aArray) -1 _ArrayConcatenate($aFullArray, $aArray[$i]) Next $aArray = $aFullArray ; Present the entire match result _ArrayDisplay($aArray, "Result")

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 AutoIt, please visit: https://www.autoitscript.com/autoit3/docs/functions/StringRegExp.htm