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

/
/
ig

Test String

Code Generator

Generated Code

// include the latest version of the regex crate in your Cargo.toml extern crate regex; use regex::Regex; fn main() { let regex = Regex::new(r"(?i)\b(FLOWLINKMEDIA ID=)").unwrap(); let string = "<FLOWLINKMEDIA ID=\"LDP_COMPLETE\"> <PART NAME=\"MAIN\"> <GRPH ZORDER=\"0\" W=\"4000\" H=\"3000\"> <SOURCE>back01.png</SOURCE> </GRPH> <GRPH ZORDER=\"1\" TP=\"#00FF00\"> <SOURCE LOCATION=\"VAR\">MKTAD:MAIN_TILE</SOURCE> </GRPH> </PART> <PART NAME=\"OMP\"> <REGION NAME=\"REQUEST_BOTTOM\"> <TEXTBOX STYLE=\"REQUEST_PROMPT\"> <SOURCE LOCATION=\"VAR\">LANG:INF_ONEMOMENT</SOURCE> </TEXTBOX> </REGION> </PART> </FLOWLINKMEDIA> <FLOWLINKMEDIA ID=\"LDP_DEPOSITMENU\"> <SM NAME=\"SMDL\" /> <PART NAME=\"MAIN\"> <GRPH ZORDER=\"0\" W=\"4000\" H=\"3000\"> <SOURCE>back01.png</SOURCE> </GRPH> <REGION NAME=\"MARKETING_BANNER\"> <GRPH ZORDER=\"1\" TP=\"#00FF00\"> <SOURCE LOCATION=\"VAR\">MKTAD:OPENER_TILE</SOURCE> </GRPH> </REGION> <REGION NAME=\"MAIN\"> <TEXTBOX STYLE=\"LINE1_LARGEPROMPT_WIDE\"> <SOURCE LOCATION=\"VAR\">LANG:PRM_INT_LDPMENU</SOURCE> </TEXTBOX> <SPEECH SCR_COMP=\"PROMPT\"> <SOURCE LOCATION=\"VAR\">LANG:TTS_PAUSE</SOURCE> </SPEECH> <TEXTBOX STYLE=\"PROMPT_SUBTEXT\"> <VARSOURCE> <SOURCE LOCATION=\"VAR\">LANG:INF_BCREFERENCE</SOURCE> <VAR NAME=\"BCTOACCT\"> <SOURCE LOCATION=\"VAR\">BUSOBJ:USERDATA\\TOACCT\\NAME_NUMBER</SOURCE> </VAR> </VARSOURCE> </TEXTBOX> <SPEECH SCR_COMP=\"PROMPT\"> <SOURCE LOCATION=\"VAR\">LANG:TTS_PAUSE</SOURCE> </SPEECH> </REGION> </PART> <PART NAME=\"NAV_BAR\"> <REGION NAME=\"NAVIGATION_BAR\"> <GRPH ZORDER=\"1\" TP=\"#00FF00\"> <SOURCE>nav_bar.png</SOURCE> </GRPH> </REGION> </PART> <PART NAME=\"CANCEL\"> <ACTIONKEY VALUE=\"CANCEL\"/> <REGION NAME=\"NAVIGATION_BAR_LEFT_BTN\" TOUCH=\"Y\"> <GRPH ZORDER=\"2\" Y=\"80\" X=\"90\"> <SOURCE>nav_exit.png</SOURCE> </GRPH> <TEXTBOX STYLE=\"NAVBAR_LEFT_OPTION\"> <SOURCE LOCATION=\"VAR\">LANG:FDK_CANCEL</SOURCE> </TEXTBOX> </REGION> </PART> <PART NAME=\"TYPE_PANEL\"> <REGION NAME=\"MAIN_PANEL\" TOUCH=\"N\"> <GRPH ZORDER=\"1\"> <SOURCE>main_panel.png</SOURCE> </GRPH> </REGION> </PART> <DISPLAYLIST LISTNAME=\"DEPTYPE\" EVENTNAME=\"FE_SELECTED\"> <POSITIONS> <POS REGION_NAME=\"MAIN_PANEL_1OF3\" TOUCH=\"Y\"> <SPITEM ITEMNAME=\"SHOW\" ENABLEINPUT=\"Y\"> <GRPH ZORDER=\"3\"> <SOURCE>primary_tile_1.png</SOURCE> </GRPH> <TEXTBOX STYLE=\"PRIMARY_TILE1_CENTER\"> <VARSOURCE LOCATION=\"VAR\"> <SOURCE>LANG:INF_LDPMENU_</SOURCE> <SOURCE LOCATION=\"DISPLAYLIST\">VALUE</SOURCE> </VARSOURCE> </TEXTBOX> </SPITEM> <SPITEM ITEMNAME=\"GHOST\" ENABLEINPUT=\"N\"> <GRPH ZORDER=\"1\" TP=\"#00FF00\"> <SOURCE>primary_tile_1_ghost.png</SOURCE> </GRPH> <TEXTBOX STYLE=\"PRIMARY_TILE1_CENTER_1OF2\"> <VARSOURCE LOCATION=\"VAR\"> <SOURCE>LANG:INF_LDPMENU_</SOURCE> <SOURCE LOCATION=\"DISPLAYLIST\">VALUE</SOURCE> </VARSOURCE> </TEXTBOX> <TEXTBOX STYLE=\"PRIMARY_TILE1_CENTER_2OF2\"> <SOURCE LOCATION=\"VAR\">LANG:MENU_TEMP_UNAVAILABLE</SOURCE> </TEXTBOX> </SPITEM> <SPITEM ITEMNAME=\"HIDE\" ENABLEINPUT=\"N\"/> <RESPONSE DISPLAYTIME=\"100\"> <GRPH ZORDER=\"0\" TP=\"#00FF00\"> <SOURCE>Highlight\\primary_tile_1.png</SOURCE> </GRPH> </RESPONSE> </POS> <POS REGION_NAME=\"MAIN_PANEL_2OF3\" TOUCH=\"Y\"> <SPITEM ITEMNAME=\"SHOW\" ENABLEINPUT=\"Y\"> <GRPH ZORDER=\"3\"> <SOURCE>primary_tile_1.png</SOURCE> </GRPH> <TEXTBOX STYLE=\"PRIMARY_TILE1_CENTER\"> <VARSOURCE LOCATION=\"VAR\"> <SOURCE>LANG:INF_LDPMENU_</SOURCE> <SOURCE LOCATION=\"DISPLAYLIST\">VALUE</SOURCE> </VARSOURCE> </TEXTBOX> </SPITEM> <SPITEM ITEMNAME=\"GHOST\" ENABLEINPUT=\"N\"> <GRPH ZORDER=\"1\" TP=\"#00FF00\"> <SOURCE>primary_tile_1_ghost.png</SOURCE> </GRPH> <TEXTBOX STYLE=\"PRIMARY_TILE1_CENTER_1OF2\"> <VARSOURCE LOCATION=\"VAR\"> <SOURCE>LANG:INF_LDPMENU_</SOURCE> <SOURCE LOCATION=\"DISPLAYLIST\">VALUE</SOURCE> </VARSOURCE> </TEXTBOX> <TEXTBOX STYLE=\"PRIMARY_TILE1_CENTER_2OF2\"> <SOURCE LOCATION=\"VAR\">LANG:MENU_TEMP_UNAVAILABLE</SOURCE> </TEXTBOX> </SPITEM> <SPITEM ITEMNAME=\"HIDE\" ENABLEINPUT=\"N\"/> <RESPONSE DISPLAYTIME=\"100\"> <GRPH ZORDER=\"0\" TP=\"#00FF00\"> <SOURCE>Highlight\\primary_tile_1.png</SOURCE> </GRPH> </RESPONSE> </POS> <POS REGION_NAME=\"MAIN_PANEL_3OF3\" TOUCH=\"Y\"> <SPITEM ITEMNAME=\"SHOW\" ENABLEINPUT=\"Y\"> <GRPH ZORDER=\"3\"> <SOURCE>primary_tile_1.png</SOURCE> </GRPH> <TEXTBOX STYLE=\"PRIMARY_TILE1_CENTER\"> <VARSOURCE LOCATION=\"VAR\"> <SOURCE>LANG:INF_LDPMENU_</SOURCE> <SOURCE LOCATION=\"DISPLAYLIST\">VALUE</SOURCE> </VARSOURCE> </TEXTBOX> </SPITEM> <SPITEM ITEMNAME=\"GHOST\" ENABLEINPUT=\"N\"> <GRPH ZORDER=\"1\" TP=\"#00FF00\"> <SOURCE>primary_tile_1_ghost.png</SOURCE> </GRPH> <TEXTBOX STYLE=\"PRIMARY_TILE1_CENTER_1OF2\"> <VARSOURCE LOCATION=\"VAR\"> <SOURCE>LANG:INF_LDPMENU_</SOURCE> <SOURCE LOCATION=\"DISPLAYLIST\">VALUE</SOURCE> </VARSOURCE> </TEXTBOX> <TEXTBOX STYLE=\"PRIMARY_TILE1_CENTER_2OF2\"> <SOURCE LOCATION=\"VAR\">LANG:MENU_TEMP_UNAVAILABLE</SOURCE> </TEXTBOX> </SPITEM> <SPITEM ITEMNAME=\"HIDE\" ENABLEINPUT=\"N\"/> <RESPONSE DISPLAYTIME=\"100\"> <GRPH ZORDER=\"0\" TP=\"#00FF00\"> <SOURCE>Highlight\\primary_tile_1.png</SOURCE> </GRPH> </RESPONSE> </POS> </POSITIONS> <SMDEFINED> <SMITEM SMNAME=\"MORE\" EVENTNAME=\"MORE\"> <GRPH ZORDER=\"1\" TP=\"#00FF00\"> <SOURCE>primary_tile_1.png</SOURCE> </GRPH> <TEXTBOX STYLE=\"PRIMARY_TILE1_CENTER\"> <SOURCE LOCATION=\"VAR\">LANG:FDK_MOREACCTS</SOURCE> </TEXTBOX> </SMITEM> </SMDEFINED> </DISPLAYLIST> </FLOWLINKMEDIA>"; // result will be an iterator over tuples containing the start and end indices for each match in the string let result = regex.captures_iter(string); for mat in result { println!("{:?}", mat); } }

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 Rust, please visit: https://docs.rs/regex/latest/regex/