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

/
/
g

Test String

Code Generator

Language

Generated Code

# coding=utf8 # the above tag defines encoding for this document and is for Python 2.x compatibility import re regex = r"(?:font)[\ ]+([A-Za-z0-9\=\:]+)[\}\ \}]" test_str = ("conky.config = {\n" "-- ------------------------- Windows Settings\n" " own_window = true,\n" " own_window_type = 'normal',\n" " own_window_transparent = false,\n" " own_window_hints = 'undecorated,sticky,below,skip_taskbar,skip_pager',\n" " own_window_argb_visual = true,\n" " own_window_argb_value = 0,\n\n" " double_buffer = true,\n" " background = true,\n\n" "-- ------------------------- Position\n" " alignment = 'bottom_left',\n\n" " minimum_width = 295,\n" " minimum_height = 155,\n" " maximum_width = 313,\n\n" " gap_x = 1252,\n" " gap_y = 155,\n\n" " border_inner_margin = 0,\n" " border_outer_margin = 0,\n" " border_width = 0,\n\n" "-- ------------------------- Font\n" " use_xft = true,\n" " xftalpha = 0.8,\n" " override_utf8_locale = true,\n\n" " draw_shades = true,\n" " default_shade_color = 'black',\n\n" " draw_borders = false,\n" " draw_outline = false,\n\n" " font = 'Monofur:bold:size=8',\n\n" "-- ------------------------- Color\n" " default_color = 'DCDCDC',\n" " color0 = '1793d0',\n" " color1 = 'DDDDDD',\n" " color2 = 'AAAAAA',\n" " color3 = '888888',\n\n" "-- ------------------------- OTHER\n" " update_interval = 1,\n\n" " lua_load = '~/.conky/ConkyBar/lua/net_graph.lua',\n" " lua_draw_hook_pre = 'main_graph',\n\n" "};\n\n" "conky.text = [[\n" "${color DCDCDC}\n" "${color DCDCDC }\n" "${if_existing /proc/net/route enp8s0}${voffset 25}${goto 50}${font}Network${image ~/.conky/ConkyBar/img/networkhigh.png -p 0,15}\n" "${goto 50}${font}Public ip: ${font Monofur:size=8}${texeci 36000 wget -qO - http://ip.tupeux.com | tail}\n" "${voffset 81}${goto 50}${font}Recieve: ${font Monofur:size=8}${downspeed enp8s0}${goto 210}${font}Send: ${font Monofur:size=8}${upspeed enp8s0}${else}${if_existing /proc/net/route wlp2s0}${voffset 25}${goto 50}${font}Network\n" "${goto 50}${font}Public ip: ${font Monofur:size=8}${texeci 36000 wget -qO - http://ip.tupeux.com | tail}${goto 210}${font}Sign: ${font Monofur:size=8}${wireless_link_qual_perc wlp2s0}%\n" "${voffset 81}${goto 50}${font}Recieve: ${font Monofur:size=8}${downspeed wlp2s0}${goto 210}${font}Send: ${font Monofur:size=8}${upspeed wlp2s0}\n" "${if_match \"${wireless_link_qual_perc wlp2s0}\"<\"33\"}${image ~/.conky/ConkyBar/img/networklow.png -p 0,15 -s 45x45}${else}${if_match \"${wireless_link_qual_perc wlp2s0}\"<\"66\"}${image ~/.conky/ConkyBar/img/networkmid.png -p 0,15}${else}${image ~/.conky/ConkyBar/img/networkhigh.png -p 0,15}${endif}${endif}${else}${voffset 27}${goto 50}${font}Network${image ~/.conky/ConkyBar/img/nonetwork.png -p 0,15}\n" "${goto 50}No connection${endif}${endif}\n" "]];") matches = re.finditer(regex, test_str) for matchNum, match in enumerate(matches, start=1): print ("Match {matchNum} was found at {start}-{end}: {match}".format(matchNum = matchNum, start = match.start(), end = match.end(), match = match.group())) for groupNum in range(0, len(match.groups())): groupNum = groupNum + 1 print ("Group {groupNum} found at {start}-{end}: {group}".format(groupNum = groupNum, start = match.start(groupNum), end = match.end(groupNum), group = match.group(groupNum))) # Note: for Python 2.7 compatibility, use ur"" to prefix the regex and u"" to prefix the test string and substitution.

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 Python, please visit: https://docs.python.org/3/library/re.html