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

Substitution

Processing...

Code Generator

Language

Generated Code

use strict; my $str = 'albatross_v7 g_coeffExit ExtBandsExitCoeff albatross_v7 g_dayFilter ExtDayNotToTrade albatross_v7 g_period ExtBandsPeriod albatross_v7 g_tradeDuration ExtTimeWindowDuration albatross_v7 g_tradeStartTime ExtTimeWindowStart double_rsi g_coeffRSIFast ExtCoeffRsiFast double_rsi g_dayFilter ExtDayNotToTrade double_rsi g_RSIDiffLevel ExtMinRsiDiff double_rsi g_RSIPeriod ExtSlowRsiPeriod double_rsi g_tradeDuration ExtTimeWindowDuration double_rsi g_tradeStartTime ExtTimeWindowStart double_rsi g_trend ExtTrendModeFilter double_rsi g_volatility ExtVolatilityModeFilter double_rsi_h4_ei g_coeffRSIFast ExtCoeffRsiFast double_rsi_h4_ei g_dayFilter ExtDayNotToTrade double_rsi_h4_ei g_exitParameter ExtExitParameter double_rsi_h4_ei g_exitType ExtExitType double_rsi_h4_ei g_RSIDiffLevel ExtMinRsiDiff double_rsi_h4_ei g_RSIPeriod ExtSlowRsiPeriod double_rsi_h4_ei g_tradeDuration ExtTimeWindowDuration double_rsi_h4_ei g_tradeStartTime ExtTimeWindowStart double_rsi_h4_ei g_trend ExtTrendModeFilter double_rsi_h4_ei g_volatility ExtVolatilityModeFilter hook g_CoeffExit ExtExitCoeff hook g_Cycle ExtCycleModeFilter hook g_CycleLevel ExtCycleLevel hook g_CyclePeriod ExtCyclePeriod hook g_Exit ExtExitType hook g_Order ExtOrderMode hook g_OrderBar ExtBarsNumber hook g_OrderPendingBar ExtOrderDeleteBar hook g_RSIPeriod ExtRsiPeriod hook g_Setup ExtEntrySetup hook g_Threshold ExtRsiThreshold hook g_Trend ExtTrendModeFilter hook g_TrendPeriod ExtTrendPeriod hook g_Volatility ExtVolatilityModeFilter hook g_TradeDuration ExtTimeWindowDuration hook g_TradeStartTime ExtTimeWindowStart metaphor_v5 g_barsNumber ExtBarsNumber metaphor_v5 g_coeffBarsExit ExtExitCoeffBars metaphor_v5 g_dayFilter ExtDayNotToTrade metaphor_v5 g_tradeDuration ExtTimeWindowDuration metaphor_v5 g_tradeStartTime ExtTimeWindowStart metaphor_v6 g_barsNumber ExtBarsNumber metaphor_v6 g_BBKCPeriod ExtBbkcPeriod metaphor_v6 g_coeffBarsExit ExtExitCoeffBars metaphor_v6 g_dayFilter ExtDayNotToTrade metaphor_v6 g_tradeDuration ExtTimeWindowDuration metaphor_v6 g_tradeStartTime ExtTimeWindowStart metaphor_v6_quick g_barsNumber ExtBarsNumber metaphor_v6_quick g_BBKCPeriod ExtBbkcPeriod metaphor_v6_quick g_coeffBarsExit ExtExitCoeffBars metaphor_v6_quick g_dayFilter ExtDayNotToTrade metaphor_v6_quick g_tradeDuration ExtTimeWindowDuration metaphor_v6_quick g_tradeStartTime ExtTimeWindowStart rsi_snr g_dayFilter ExtDayNotToTrade rsi_snr g_RSIPeriod ExtRsiPeriod rsi_snr g_SNRLevel ExtSnrLevel rsi_snr g_SNRPeriod ExtSnrPeriod rsi_snr g_tradeDuration ExtTimeWindowDuration rsi_snr g_tradeStartTime ExtTimeWindowStart rsi_snr g_trend ExtTrendModeFilter rsi_snr g_volatility ExtVolatilityModeFilter rsi_snr_h1_ei g_dayFilter ExtDayNotToTrade rsi_snr_h1_ei g_exitParameter ExtExitParameter rsi_snr_h1_ei g_exitType ExtExitType rsi_snr_h1_ei g_RSIPeriod ExtRsiPeriod rsi_snr_h1_ei g_SNRLevel ExtSnrLevel rsi_snr_h1_ei g_SNRPeriod ExtSnrPeriod rsi_snr_h1_ei g_tradeDuration ExtTimeWindowDuration rsi_snr_h1_ei g_tradeStartTime ExtTimeWindowStart rsi_snr_h1_ei g_trend ExtTrendModeFilter rsi_snr_h1_ei g_volatility ExtVolatilityModeFilter rush_v2_h1 g_counter ExtEntrySignalCounter rush_v2_h1 g_dayFilter ExtDayNotToTrade rush_v2_h1 g_exitBar ExtExitBar rush_v2_h1 g_tradeDuration ExtTimeWindowDuration rush_v2_h1 g_tradeStartTime ExtTimeWindowStart super_smoother_ei g_dayFilter ExtDayNotToTrade super_smoother_ei g_DiffPeriod ExtRsiPeriodDiff super_smoother_ei g_exitParameter ExtExitParameter super_smoother_ei g_exitType ExtExitType super_smoother_ei g_PeriodFast ExtFastRsiPeriod super_smoother_ei g_tradeDuration ExtTimeWindowDuration super_smoother_ei g_tradeStartTime ExtTimeWindowStart super_smoother_ei g_trend ExtTrendModeFilter super_smoother_ei g_volatility ExtVolatilityModeFilter'; my $regex = qr/([\w_]+)\t([\w_]+)\t([\w_]+)/mp; my $subst = 'update t_strategy\\n set t_strategy_parameters = replace(t_strategy_parameters, \'$2\', \'$3\')\\n where t_strategy_ea = \'$1\' and\\n t_strategy_parameters like \'%$2%\' and\\n t_strategy_version = \'1.1\';'; my $result = $str =~ s/$regex/$subst/rg; print "The result of the substitution is' $result\n";

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