diff --git a/package.json b/package.json
index b5f0085..edfc4e3 100644
--- a/package.json
+++ b/package.json
@@ -29,11 +29,11 @@
   "dependencies": {},
   "devDependencies": {
     "@aureooms/js-itertools": "4.0.0",
-    "@babel/cli": "7.10.4",
-    "@babel/core": "7.10.4",
+    "@babel/cli": "7.10.5",
+    "@babel/core": "7.10.5",
     "@babel/polyfill": "7.10.4",
     "@babel/preset-env": "7.10.4",
-    "@babel/register": "7.10.4",
+    "@babel/register": "7.10.5",
     "ava": "3.10.0",
     "coveralls": "3.1.0",
     "esdoc": "1.1.0",
diff --git a/yarn.lock b/yarn.lock
index 57698ec..ca00e5a 100644
--- a/yarn.lock
+++ b/yarn.lock
@@ -22,16 +22,16 @@
     "@aureooms/js-collections-deque" "^4.0.0"
     "@aureooms/js-error" "^4.0.0"
 
-"@babel/cli@7.10.4":
-  version "7.10.4"
-  resolved "https://registry.yarnpkg.com/@babel/cli/-/cli-7.10.4.tgz#ba38ad6d0b4b772a67b106934b7c33d656031896"
-  integrity sha512-xX99K4V1BzGJdQANK5cwK+EpF1vP9gvqhn+iWvG+TubCjecplW7RSQimJ2jcCvu6fnK5pY6mZMdu6EWTj32QVA==
+"@babel/cli@7.10.5":
+  version "7.10.5"
+  resolved "https://registry.yarnpkg.com/@babel/cli/-/cli-7.10.5.tgz#57df2987c8cf89d0fc7d4b157ec59d7619f1b77a"
+  integrity sha512-j9H9qSf3kLdM0Ao3aGPbGZ73mEA9XazuupcS6cDGWuiyAcANoguhP0r2Lx32H5JGw4sSSoHG3x/mxVnHgvOoyA==
   dependencies:
     commander "^4.0.1"
     convert-source-map "^1.1.0"
     fs-readdir-recursive "^1.1.0"
     glob "^7.0.0"
-    lodash "^4.17.13"
+    lodash "^4.17.19"
     make-dir "^2.1.0"
     slash "^2.0.0"
     source-map "^0.5.0"
@@ -61,24 +61,24 @@
     invariant "^2.2.4"
     semver "^5.5.0"
 
-"@babel/core@7.10.4":
-  version "7.10.4"
-  resolved "https://registry.yarnpkg.com/@babel/core/-/core-7.10.4.tgz#780e8b83e496152f8dd7df63892b2e052bf1d51d"
-  integrity sha512-3A0tS0HWpy4XujGc7QtOIHTeNwUgWaZc/WuS5YQrfhU67jnVmsD6OGPc1AKHH0LJHQICGncy3+YUjIhVlfDdcA==
+"@babel/core@7.10.5":
+  version "7.10.5"
+  resolved "https://registry.yarnpkg.com/@babel/core/-/core-7.10.5.tgz#1f15e2cca8ad9a1d78a38ddba612f5e7cdbbd330"
+  integrity sha512-O34LQooYVDXPl7QWCdW9p4NR+QlzOr7xShPPJz8GsuCU3/8ua/wqTr7gmnxXv+WBESiGU/G5s16i6tUvHkNb+w==
   dependencies:
     "@babel/code-frame" "^7.10.4"
-    "@babel/generator" "^7.10.4"
-    "@babel/helper-module-transforms" "^7.10.4"
+    "@babel/generator" "^7.10.5"
+    "@babel/helper-module-transforms" "^7.10.5"
     "@babel/helpers" "^7.10.4"
-    "@babel/parser" "^7.10.4"
+    "@babel/parser" "^7.10.5"
     "@babel/template" "^7.10.4"
-    "@babel/traverse" "^7.10.4"
-    "@babel/types" "^7.10.4"
+    "@babel/traverse" "^7.10.5"
+    "@babel/types" "^7.10.5"
     convert-source-map "^1.7.0"
     debug "^4.1.0"
     gensync "^1.0.0-beta.1"
     json5 "^2.1.2"
-    lodash "^4.17.13"
+    lodash "^4.17.19"
     resolve "^1.3.2"
     semver "^5.4.1"
     source-map "^0.5.0"
@@ -125,6 +125,15 @@
     lodash "^4.17.13"
     source-map "^0.5.0"
 
+"@babel/generator@^7.10.5":
+  version "7.10.5"
+  resolved "https://registry.yarnpkg.com/@babel/generator/-/generator-7.10.5.tgz#1b903554bc8c583ee8d25f1e8969732e6b829a69"
+  integrity sha512-3vXxr3FEW7E7lJZiWQ3bM4+v/Vyr9C+hpolQ8BGFr9Y8Ri2tFLWTixmwKBafDujO1WVah4fhZBeU1bieKdghig==
+  dependencies:
+    "@babel/types" "^7.10.5"
+    jsesc "^2.5.1"
+    source-map "^0.5.0"
+
 "@babel/helper-annotate-as-pure@^7.10.1":
   version "7.10.1"
   resolved "https://registry.yarnpkg.com/@babel/helper-annotate-as-pure/-/helper-annotate-as-pure-7.10.1.tgz#f6d08acc6f70bbd59b436262553fb2e259a1a268"
@@ -298,6 +307,19 @@
     "@babel/types" "^7.10.4"
     lodash "^4.17.13"
 
+"@babel/helper-module-transforms@^7.10.5":
+  version "7.10.5"
+  resolved "https://registry.yarnpkg.com/@babel/helper-module-transforms/-/helper-module-transforms-7.10.5.tgz#120c271c0b3353673fcdfd8c053db3c544a260d6"
+  integrity sha512-4P+CWMJ6/j1W915ITJaUkadLObmCRRSC234uctJfn/vHrsLNxsR8dwlcXv9ZhJWzl77awf+mWXSZEKt5t0OnlA==
+  dependencies:
+    "@babel/helper-module-imports" "^7.10.4"
+    "@babel/helper-replace-supers" "^7.10.4"
+    "@babel/helper-simple-access" "^7.10.4"
+    "@babel/helper-split-export-declaration" "^7.10.4"
+    "@babel/template" "^7.10.4"
+    "@babel/types" "^7.10.5"
+    lodash "^4.17.19"
+
 "@babel/helper-optimise-call-expression@^7.10.1":
   version "7.10.1"
   resolved "https://registry.yarnpkg.com/@babel/helper-optimise-call-expression/-/helper-optimise-call-expression-7.10.1.tgz#b4a1f2561870ce1247ceddb02a3860fa96d72543"
@@ -463,6 +485,11 @@
   resolved "https://registry.yarnpkg.com/@babel/parser/-/parser-7.10.4.tgz#9eedf27e1998d87739fb5028a5120557c06a1a64"
   integrity sha512-8jHII4hf+YVDsskTF6WuMB3X4Eh+PsUkC2ljq22so5rHvH+T8BzyL94VOdyFLNR8tBSVXOTbNHOKpR4TfRxVtA==
 
+"@babel/parser@^7.10.5":
+  version "7.10.5"
+  resolved "https://registry.yarnpkg.com/@babel/parser/-/parser-7.10.5.tgz#e7c6bf5a7deff957cec9f04b551e2762909d826b"
+  integrity sha512-wfryxy4bE1UivvQKSQDU4/X6dr+i8bctjUjj8Zyt3DQy7NtPizJXT8M52nqpNKL+nq2PW8lxk4ZqLj0fD4B4hQ==
+
 "@babel/plugin-proposal-async-generator-functions@^7.10.4":
   version "7.10.4"
   resolved "https://registry.yarnpkg.com/@babel/plugin-proposal-async-generator-functions/-/plugin-proposal-async-generator-functions-7.10.4.tgz#4b65abb3d9bacc6c657aaa413e56696f9f170fc6"
@@ -979,13 +1006,13 @@
     "@babel/types" "^7.4.4"
     esutils "^2.0.2"
 
-"@babel/register@7.10.4":
-  version "7.10.4"
-  resolved "https://registry.yarnpkg.com/@babel/register/-/register-7.10.4.tgz#53004ba8b04c4af3cbd84508e03ad150669746e4"
-  integrity sha512-whHmgGiWNVyTVnYTSawtDWhaeYsc+noeU8Rmi+MPnbGhDYmr5QpEDMrQcIA07D2RUv0BlThPcN89XcHCqq/O4g==
+"@babel/register@7.10.5":
+  version "7.10.5"
+  resolved "https://registry.yarnpkg.com/@babel/register/-/register-7.10.5.tgz#354f3574895f1307f79efe37a51525e52fd38d89"
+  integrity sha512-eYHdLv43nyvmPn9bfNfrcC4+iYNwdQ8Pxk1MFJuU/U5LpSYl/PH4dFMazCYZDFVi8ueG3shvO+AQfLrxpYulQw==
   dependencies:
     find-cache-dir "^2.0.0"
-    lodash "^4.17.13"
+    lodash "^4.17.19"
     make-dir "^2.1.0"
     pirates "^4.0.0"
     source-map-support "^0.5.16"
@@ -1053,6 +1080,21 @@
     globals "^11.1.0"
     lodash "^4.17.13"
 
+"@babel/traverse@^7.10.5":
+  version "7.10.5"
+  resolved "https://registry.yarnpkg.com/@babel/traverse/-/traverse-7.10.5.tgz#77ce464f5b258be265af618d8fddf0536f20b564"
+  integrity sha512-yc/fyv2gUjPqzTz0WHeRJH2pv7jA9kA7mBX2tXl/x5iOE81uaVPuGPtaYk7wmkx4b67mQ7NqI8rmT2pF47KYKQ==
+  dependencies:
+    "@babel/code-frame" "^7.10.4"
+    "@babel/generator" "^7.10.5"
+    "@babel/helper-function-name" "^7.10.4"
+    "@babel/helper-split-export-declaration" "^7.10.4"
+    "@babel/parser" "^7.10.5"
+    "@babel/types" "^7.10.5"
+    debug "^4.1.0"
+    globals "^11.1.0"
+    lodash "^4.17.19"
+
 "@babel/types@^7.10.1", "@babel/types@^7.10.2", "@babel/types@^7.4.4":
   version "7.10.2"
   resolved "https://registry.yarnpkg.com/@babel/types/-/types-7.10.2.tgz#30283be31cad0dbf6fb00bd40641ca0ea675172d"
@@ -1071,6 +1113,15 @@
     lodash "^4.17.13"
     to-fast-properties "^2.0.0"
 
+"@babel/types@^7.10.5":
+  version "7.10.5"
+  resolved "https://registry.yarnpkg.com/@babel/types/-/types-7.10.5.tgz#d88ae7e2fde86bfbfe851d4d81afa70a997b5d15"
+  integrity sha512-ixV66KWfCI6GKoA/2H9v6bQdbfXEwwpOdQ8cRvb4F+eyvhlaHxWFMQB4+3d9QFJXZsiiiqVrewNV0DFEQpyT4Q==
+  dependencies:
+    "@babel/helper-validator-identifier" "^7.10.4"
+    lodash "^4.17.19"
+    to-fast-properties "^2.0.0"
+
 "@concordance/react@^2.0.0":
   version "2.0.0"
   resolved "https://registry.yarnpkg.com/@concordance/react/-/react-2.0.0.tgz#aef913f27474c53731f4fd79cc2f54897de90fde"
@@ -4263,6 +4314,11 @@ lodash@^4.1.0, lodash@^4.15.0, lodash@^4.17.12, lodash@^4.17.13, lodash@^4.17.15
   resolved "https://registry.yarnpkg.com/lodash/-/lodash-4.17.15.tgz#b447f6670a0455bbfeedd11392eff330ea097548"
   integrity sha512-8xOcRHvCjnocdS5cpwXQXVzmmh5e5+saE2QGoeQmbKmRS6J3VQppPOIt0MnmE+4xlZoumy0GPG0D0MVIQbNA1A==
 
+lodash@^4.17.19:
+  version "4.17.19"
+  resolved "https://registry.yarnpkg.com/lodash/-/lodash-4.17.19.tgz#e48ddedbe30b3321783c5b4301fbd353bc1e4a4b"
+  integrity sha512-JNvd8XER9GQX0v2qJgsaN/mzFCNA5BRe/j8JN9d+tWyGLSodKQHKFicdwNYzWwI3wjRnaKPsGj1XkBjx/F96DQ==
+
 log-driver@^1.2.7:
   version "1.2.7"
   resolved "https://registry.yarnpkg.com/log-driver/-/log-driver-1.2.7.tgz#63b95021f0702fedfa2c9bb0a24e7797d71871d8"