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

const regex = /(?:font)[\ ]+([A-Za-z0-9\=\:]+)[\}\ \}]/g; // Alternative syntax using RegExp constructor // const regex = new RegExp('(?:font)[\\ ]+([A-Za-z0-9\\=\\:]+)[\\}\\ \\}]', 'g') const str = `conky.config = { -- ------------------------- Windows Settings own_window = true, own_window_type = 'normal', own_window_transparent = false, own_window_hints = 'undecorated,sticky,below,skip_taskbar,skip_pager', own_window_argb_visual = true, own_window_argb_value = 0, double_buffer = true, background = true, -- ------------------------- Position alignment = 'bottom_left', minimum_width = 295, minimum_height = 155, maximum_width = 313, gap_x = 1252, gap_y = 155, border_inner_margin = 0, border_outer_margin = 0, border_width = 0, -- ------------------------- Font use_xft = true, xftalpha = 0.8, override_utf8_locale = true, draw_shades = true, default_shade_color = 'black', draw_borders = false, draw_outline = false, font = 'Monofur:bold:size=8', -- ------------------------- Color default_color = 'DCDCDC', color0 = '1793d0', color1 = 'DDDDDD', color2 = 'AAAAAA', color3 = '888888', -- ------------------------- OTHER update_interval = 1, lua_load = '~/.conky/ConkyBar/lua/net_graph.lua', lua_draw_hook_pre = 'main_graph', }; conky.text = [[ \${color DCDCDC} \${color DCDCDC } \${if_existing /proc/net/route enp8s0}\${voffset 25}\${goto 50}\${font}Network\${image ~/.conky/ConkyBar/img/networkhigh.png -p 0,15} \${goto 50}\${font}Public ip: \${font Monofur:size=8}\${texeci 36000 wget -qO - http://ip.tupeux.com | tail} \${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 \${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}% \${voffset 81}\${goto 50}\${font}Recieve: \${font Monofur:size=8}\${downspeed wlp2s0}\${goto 210}\${font}Send: \${font Monofur:size=8}\${upspeed wlp2s0} \${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} \${goto 50}No connection\${endif}\${endif} ]];`; // Reset `lastIndex` if this regex is defined globally // regex.lastIndex = 0; let m; while ((m = regex.exec(str)) !== null) { // This is necessary to avoid infinite loops with zero-width matches if (m.index === regex.lastIndex) { regex.lastIndex++; } // The result can be accessed through the `m`-variable. m.forEach((match, groupIndex) => { console.log(`Found match, group ${groupIndex}: ${match}`); }); }

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 JavaScript, please visit: https://developer.mozilla.org/en/docs/Web/JavaScript/Guide/Regular_Expressions