diff --git a/package-lock.json b/package-lock.json
index 5e83268..73d15f3 100644
--- a/package-lock.json
+++ b/package-lock.json
@@ -1,6 +1,6 @@
 {
   "name": "sd-expression-engine",
-  "version": "0.1.14",
+  "version": "0.1.15",
   "lockfileVersion": 1,
   "requires": true,
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@@ -3762,7 +3762,7 @@
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-          "resolved": "http://registry.npmjs.org/util/-/util-0.10.3.tgz",
+          "resolved": "https://registry.npmjs.org/util/-/util-0.10.3.tgz",
           "integrity": "sha1-evsa/lCAUkZInj23/g7TeTNqwPk=",
           "dev": true,
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@@ -3881,7 +3881,7 @@
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         "chalk": {
           "version": "1.1.3",
-          "resolved": "http://registry.npmjs.org/chalk/-/chalk-1.1.3.tgz",
+          "resolved": "https://registry.npmjs.org/chalk/-/chalk-1.1.3.tgz",
           "integrity": "sha1-qBFcVeSnAv5NFQq9OHKCKn4J/Jg=",
           "dev": true,
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@@ -6964,7 +6964,8 @@
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           "version": "2.1.1",
           "bundled": true,
-          "dev": true
+          "dev": true,
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@@ -6985,12 +6986,14 @@
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           "version": "1.0.0",
           "bundled": true,
-          "dev": true
+          "dev": true,
+          "optional": true
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         "brace-expansion": {
           "version": "1.1.11",
           "bundled": true,
           "dev": true,
+          "optional": true,
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@@ -7005,17 +7008,20 @@
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           "version": "1.1.0",
           "bundled": true,
-          "dev": true
+          "dev": true,
+          "optional": true
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           "version": "0.0.1",
           "bundled": true,
-          "dev": true
+          "dev": true,
+          "optional": true
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           "version": "1.1.0",
           "bundled": true,
-          "dev": true
+          "dev": true,
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         "core-util-is": {
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@@ -7132,7 +7138,8 @@
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           "version": "2.0.3",
           "bundled": true,
-          "dev": true
+          "dev": true,
+          "optional": true
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@@ -7144,6 +7151,7 @@
           "version": "1.0.0",
           "bundled": true,
           "dev": true,
+          "optional": true,
           "requires": {
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           }
@@ -7158,6 +7166,7 @@
           "version": "3.0.4",
           "bundled": true,
           "dev": true,
+          "optional": true,
           "requires": {
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@@ -7165,12 +7174,14 @@
         "minimist": {
           "version": "0.0.8",
           "bundled": true,
-          "dev": true
+          "dev": true,
+          "optional": true
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         "minipass": {
           "version": "2.3.5",
           "bundled": true,
           "dev": true,
+          "optional": true,
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             "yallist": "^3.0.0"
@@ -7189,6 +7200,7 @@
           "version": "0.5.1",
           "bundled": true,
           "dev": true,
+          "optional": true,
           "requires": {
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@@ -7269,7 +7281,8 @@
         "number-is-nan": {
           "version": "1.0.1",
           "bundled": true,
-          "dev": true
+          "dev": true,
+          "optional": true
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@@ -7281,6 +7294,7 @@
           "version": "1.4.0",
           "bundled": true,
           "dev": true,
+          "optional": true,
           "requires": {
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@@ -7366,7 +7380,8 @@
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           "version": "5.1.2",
           "bundled": true,
-          "dev": true
+          "dev": true,
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@@ -7402,6 +7417,7 @@
           "version": "1.0.2",
           "bundled": true,
           "dev": true,
+          "optional": true,
           "requires": {
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@@ -7421,6 +7437,7 @@
           "version": "3.0.1",
           "bundled": true,
           "dev": true,
+          "optional": true,
           "requires": {
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@@ -7432,18 +7449,32 @@
           "optional": true
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         "tar": {
-          "version": "4.4.8",
-          "bundled": true,
+          "version": "4.4.15",
+          "resolved": "https://registry.npmjs.org/tar/-/tar-4.4.15.tgz",
+          "integrity": "sha512-ItbufpujXkry7bHH9NpQyTXPbJ72iTlXgkBAYsAjDXk3Ds8t/3NfO5P4xZGy7u+sYuQUbimgzswX4uQIEeNVOA==",
           "dev": true,
           "optional": true,
           "requires": {
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             "fs-minipass": "^1.2.5",
-            "minipass": "^2.3.4",
-            "minizlib": "^1.1.1",
+            "minipass": "^2.8.6",
+            "minizlib": "^1.2.1",
             "mkdirp": "^0.5.0",
             "safe-buffer": "^5.1.2",
-            "yallist": "^3.0.2"
+            "yallist": "^3.0.3"
+          },
+          "dependencies": {
+            "minipass": {
+              "version": "2.9.0",
+              "resolved": "https://registry.npmjs.org/minipass/-/minipass-2.9.0.tgz",
+              "integrity": "sha512-wxfUjg9WebH+CUDX/CdbRlh5SmfZiy/hpkxaRI16Y9W56Pa75sWgd/rvFilSgrauD9NyFymP/+JFV3KwzIsJeg==",
+              "dev": true,
+              "optional": true,
+              "requires": {
+                "safe-buffer": "^5.1.2",
+                "yallist": "^3.0.0"
+              }
+            }
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         "util-deprecate": {
@@ -7464,12 +7495,14 @@
         "wrappy": {
           "version": "1.0.2",
           "bundled": true,
-          "dev": true
+          "dev": true,
+          "optional": true
         },
         "yallist": {
           "version": "3.0.3",
           "bundled": true,
-          "dev": true
+          "dev": true,
+          "optional": true
         }
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@@ -7788,7 +7821,7 @@
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         "load-json-file": {
           "version": "1.1.0",
-          "resolved": "http://registry.npmjs.org/load-json-file/-/load-json-file-1.1.0.tgz",
+          "resolved": "https://registry.npmjs.org/load-json-file/-/load-json-file-1.1.0.tgz",
           "integrity": "sha1-lWkFcI1YtLq0wiYbBPWfMcmTdMA=",
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@@ -7830,7 +7863,7 @@
         },
         "pify": {
           "version": "2.3.0",
-          "resolved": "http://registry.npmjs.org/pify/-/pify-2.3.0.tgz",
+          "resolved": "https://registry.npmjs.org/pify/-/pify-2.3.0.tgz",
           "integrity": "sha1-7RQaasBDqEnqWISY59yosVMw6Qw=",
           "dev": true
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@@ -8064,7 +8097,7 @@
         },
         "chalk": {
           "version": "1.1.3",
-          "resolved": "http://registry.npmjs.org/chalk/-/chalk-1.1.3.tgz",
+          "resolved": "https://registry.npmjs.org/chalk/-/chalk-1.1.3.tgz",
           "integrity": "sha1-qBFcVeSnAv5NFQq9OHKCKn4J/Jg=",
           "dev": true,
           "requires": {
@@ -8086,7 +8119,7 @@
         },
         "kind-of": {
           "version": "1.1.0",
-          "resolved": "http://registry.npmjs.org/kind-of/-/kind-of-1.1.0.tgz",
+          "resolved": "https://registry.npmjs.org/kind-of/-/kind-of-1.1.0.tgz",
           "integrity": "sha1-FAo9LUGjbS78+pN3tiwk+ElaXEQ=",
           "dev": true
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@@ -8213,7 +8246,7 @@
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         "chalk": {
           "version": "1.1.3",
-          "resolved": "http://registry.npmjs.org/chalk/-/chalk-1.1.3.tgz",
+          "resolved": "https://registry.npmjs.org/chalk/-/chalk-1.1.3.tgz",
           "integrity": "sha1-qBFcVeSnAv5NFQq9OHKCKn4J/Jg=",
           "dev": true,
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@@ -8493,7 +8526,7 @@
       "dependencies": {
         "commander": {
           "version": "2.9.0",
-          "resolved": "http://registry.npmjs.org/commander/-/commander-2.9.0.tgz",
+          "resolved": "https://registry.npmjs.org/commander/-/commander-2.9.0.tgz",
           "integrity": "sha1-nJkJQXbhIkDLItbFFGCYQA/g99Q=",
           "dev": true,
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@@ -10717,6 +10750,11 @@
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+    "mkdirp": {
+      "version": "1.0.4",
+      "resolved": "https://registry.npmjs.org/mkdirp/-/mkdirp-1.0.4.tgz",
+      "integrity": "sha512-vVqVZQyf3WLx2Shd0qJ9xuvqgAyKPLAiqITEtqW0oIUjzo3PePDd6fW9iFz30ef7Ysp/oiWqbhszeGWW2T6Gzw=="
+    },
     "mkdirp-classic": {
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       "resolved": "https://registry.npmjs.org/mkdirp-classic/-/mkdirp-classic-0.5.3.tgz",
@@ -10777,7 +10815,7 @@
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           "version": "1.1.14",
-          "resolved": "http://registry.npmjs.org/readable-stream/-/readable-stream-1.1.14.tgz",
+          "resolved": "https://registry.npmjs.org/readable-stream/-/readable-stream-1.1.14.tgz",
           "integrity": "sha1-fPTFTvZI44EwhMY23SB54WbAgdk=",
           "dev": true,
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@@ -10941,9 +10979,9 @@
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-          "resolved": "https://registry.npmjs.org/tar/-/tar-4.4.13.tgz",
-          "integrity": "sha512-w2VwSrBoHa5BsSyH+KxEqeQBAllHhccyMFVHtGtdMpF4W7IRWfZjFiQceJPChOeTsSDVUpER2T8FA93pr0L+QA==",
+          "version": "4.4.15",
+          "resolved": "https://registry.npmjs.org/tar/-/tar-4.4.15.tgz",
+          "integrity": "sha512-ItbufpujXkry7bHH9NpQyTXPbJ72iTlXgkBAYsAjDXk3Ds8t/3NfO5P4xZGy7u+sYuQUbimgzswX4uQIEeNVOA==",
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@@ -11677,7 +11715,7 @@
       "dependencies": {
         "minimist": {
           "version": "0.0.10",
-          "resolved": "http://registry.npmjs.org/minimist/-/minimist-0.0.10.tgz",
+          "resolved": "https://registry.npmjs.org/minimist/-/minimist-0.0.10.tgz",
           "integrity": "sha1-3j+YVD2/lggr5IrRoMfNqDYwHc8=",
           "dev": true
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@@ -12464,7 +12502,7 @@
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-      "resolved": "http://registry.npmjs.org/readable-stream/-/readable-stream-2.3.6.tgz",
+      "resolved": "https://registry.npmjs.org/readable-stream/-/readable-stream-2.3.6.tgz",
       "integrity": "sha512-tQtKA9WIAhBF3+VLAseyMqZeBjW0AHJoxOtYqSUZNJxauErmLbVm2FW1y+J/YA9dUrAC39ITejlZWhVIwawkKw==",
       "requires": {
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@@ -14066,7 +14104,7 @@
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     "strip-ansi": {
       "version": "3.0.1",
-      "resolved": "http://registry.npmjs.org/strip-ansi/-/strip-ansi-3.0.1.tgz",
+      "resolved": "https://registry.npmjs.org/strip-ansi/-/strip-ansi-3.0.1.tgz",
       "integrity": "sha1-ajhfuIU9lS1f8F0Oiq+UJ43GPc8=",
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@@ -14139,32 +14177,27 @@
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-      "resolved": "https://registry.npmjs.org/tar/-/tar-6.0.2.tgz",
-      "integrity": "sha512-Glo3jkRtPcvpDlAs/0+hozav78yoXKFr+c4wgw62NNMO3oo4AaJdCo21Uu7lcwr55h39W2XD1LMERc64wtbItg==",
+      "version": "6.1.6",
+      "resolved": "https://registry.npmjs.org/tar/-/tar-6.1.6.tgz",
+      "integrity": "sha512-oaWyu5dQbHaYcyZCTfyPpC+VmI62/OM2RTUYavTk1MDr1cwW5Boi3baeYQKiZbY2uSQJGr+iMOzb/JFxLrft+g==",
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         "chownr": "^2.0.0",
         "fs-minipass": "^2.0.0",
         "minipass": "^3.0.0",
-        "minizlib": "^2.1.0",
+        "minizlib": "^2.1.1",
         "mkdirp": "^1.0.3",
         "yallist": "^4.0.0"
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       "dependencies": {
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-          "resolved": "https://registry.npmjs.org/minizlib/-/minizlib-2.1.0.tgz",
-          "integrity": "sha512-EzTZN/fjSvifSX0SlqUERCN39o6T40AMarPbv0MrarSFtIITCBh7bi+dU8nxGFHuqs9jdIAeoYoKuQAAASsPPA==",
+          "version": "2.1.2",
+          "resolved": "https://registry.npmjs.org/minizlib/-/minizlib-2.1.2.tgz",
+          "integrity": "sha512-bAxsR8BVfj60DWXHE3u30oHzfl4G7khkSuPW+qvpd7jFRHm7dLxOjUk1EHACJ/hxLY8phGJ0YhYHZo7jil7Qdg==",
           "requires": {
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-        "mkdirp": {
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-          "resolved": "https://registry.npmjs.org/mkdirp/-/mkdirp-1.0.4.tgz",
-          "integrity": "sha512-vVqVZQyf3WLx2Shd0qJ9xuvqgAyKPLAiqITEtqW0oIUjzo3PePDd6fW9iFz30ef7Ysp/oiWqbhszeGWW2T6Gzw=="
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@@ -15301,7 +15334,7 @@
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       "version": "2.1.0",
-      "resolved": "http://registry.npmjs.org/wrap-ansi/-/wrap-ansi-2.1.0.tgz",
+      "resolved": "https://registry.npmjs.org/wrap-ansi/-/wrap-ansi-2.1.0.tgz",
       "integrity": "sha1-2Pw9KE3QV5T+hJc8rs3Rz4JP3YU=",
       "dev": true,
       "requires": {