diff --git a/dist/lodash.underscore.js b/dist/lodash.underscore.js
index 840ddfe2a..04347b7ba 100644
--- a/dist/lodash.underscore.js
+++ b/dist/lodash.underscore.js
@@ -4154,7 +4154,9 @@
    * // => true
    */
   function isRegExp(value) {
-    return value && typeof value == 'object' && toString.call(value) == regexpClass || false;
+    var type = typeof value;
+    return value && (type == 'function' || type == 'object') &&
+      toString.call(value) == regexpClass || false;
   }
 
   /**
diff --git a/dist/lodash.underscore.min.js b/dist/lodash.underscore.min.js
index 8f51f95e1..f51c1a28b 100644
--- a/dist/lodash.underscore.min.js
+++ b/dist/lodash.underscore.min.js
@@ -33,7 +33,7 @@ if(null==r&&typeof i=="number")for(;++o<i;)t=n[o],t<u&&(u=t);else r=Z(r,t,3),p(n
 if(!H(n))throw new TypeError;return false===t?e=false:J(t)&&(e="leading"in t?t.leading:e,u="trailing"in t?t.trailing:u),t={},t.leading=e,t.maxWait=r,t.trailing=u,P(n,r,t)},o.times=function(n,r,t){n=-1<(n=+n)?n:0;var e=-1,u=Array(n);for(r=a(r,t,1);++e<n;)u[e]=r(e);return u},o.toArray=function(n){return ft(n)?O(n):n&&typeof n.length=="number"?$(n):Y(n)},o.union=function(){return m(g(arguments,true,true))},o.uniq=k,o.values=Y,o.where=it,o.without=function(n){return l(n,O(arguments,1))},o.wrap=function(n,r){return _(r,fr,null,[n])
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-},o.isNull=function(n){return null===n},o.isNumber=K,o.isObject=J,o.isRegExp=function(n){return n&&typeof n=="object"&&$r.call(n)==wr||false},o.isString=L,o.isUndefined=function(n){return typeof n=="undefined"},o.lastIndexOf=function(n,r,t){var e=n?n.length:0;for(typeof t=="number"&&(e=(0>t?Lr(0,e+t):Qr(t,e-1))+1);e--;)if(n[e]===r)return e;return-1},o.mixin=tr,o.noConflict=function(){return Or._=Rr,this},o.now=ct,o.random=function(n,r){return null==n&&null==r&&(r=1),n=+n||0,null==r?(r=n,n=0):r=+r||0,n+Dr(Yr()*(r-n+1))
+},o.isNull=function(n){return null===n},o.isNumber=K,o.isObject=J,o.isRegExp=function(n){var r=typeof n;return n&&("function"==r||"object"==r)&&$r.call(n)==wr||false},o.isString=L,o.isUndefined=function(n){return typeof n=="undefined"},o.lastIndexOf=function(n,r,t){var e=n?n.length:0;for(typeof t=="number"&&(e=(0>t?Lr(0,e+t):Qr(t,e-1))+1);e--;)if(n[e]===r)return e;return-1},o.mixin=tr,o.noConflict=function(){return Or._=Rr,this},o.now=ct,o.random=function(n,r){return null==n&&null==r&&(r=1),n=+n||0,null==r?(r=n,n=0):r=+r||0,n+Dr(Yr()*(r-n+1))
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 }),a+="';",i||(a="with(obj||{}){"+a+"}"),a="function("+(i||"obj")+"){var __t,__p='',__j=Array.prototype.join;function print(){__p+=__j.call(arguments,'')}"+a+"return __p}";try{var c=Function("_","return "+a)(u)}catch(l){throw l.source=a,l}return r?c(r):(c.source=a,c)},o.unescape=function(n){return null==n?"":(n+="",0>n.indexOf(";")?n:n.replace(lr,u))},o.uniqueId=function(n){var r=++cr+"";return n?n+r:r},o.all=q,o.any=z,o.detect=B,o.findWhere=B,o.foldl=M,o.foldr=D,o.include=N,o.inject=M,o.first=A,o.last=function(n,r,t){var e=n?n.length:0;
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