re = /^([ \t]*)import [*] as (\w+) from (?:(['])((?:(?:\.)+|[^\n\r'\\]+)+)[']|(["])((?:(?:\.)+|[^\n\r'\\]+)+)["])/m
str = 'import * as Atblock from "./atblock"
import * as Atrule from "./atrule"
import * as Supports from "./supports"
import * as Node from \'./node\';
import * as Root from \'./root\'
import Null from \'./null\'
import * as Each from \'./each\'
import * as If from \'./if\'
import * as Call from \'./call\'
import * as UnaryOp from \'./unaryop\'
import * as BinOp from \'./binop\'
import * as Ternary from \'./ternary\'
import * as Block from \'./block\'
import * as Unit from \'./unit\'
import * as String from \'./string\'
import * as HSLA from \'./hsla\'
import * as RGBA from \'./rgba\'
import * as Ident from \'./ident\'
import * as Group from \'./group\'
import * as Literal from \'./literal\'
import * as Boolean from \'./boolean\'
import * as Return from \'./return\'
import * as Media from \'./media\'
import * as QueryList from \'./query-list\'
import * as Query from \'./query\'
import * as Feature from \'./feature\'
import * as Params from \'./params\'
import * as Comment from \'./comment\'
import * as Keyframes from \'./keyframes\'
import * as Member from \'./member\'
import * as Charset from \'./charset\'
import * as Namespace from \'./namespace\'
import * as Import from \'./import\'
import * as Extend from \'./extend\'
import * as Object from \'./object\'
import * as Function from \'./function\'
import * as Property from \'./property\'
import * as Selector from \'./selector\'
import * as Expression from \'./expression\'
import * as Arguments from \'./arguments\'
import * as Atblock from \'./atblock\'
import * as Atrule from \'./atrule\'
import * as Supports from \'./supports\'
'
subst = '$1import $2 from $3$5$6$4$3$5'
result = str.gsub(re, subst)
# Print the result of the substitution
puts 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 Ruby, please visit: http://ruby-doc.org/core-2.2.0/Regexp.html