Add node_modules

node_modules/property-expr/README.md

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+# expr
+
+Tiny property path utilities, including path parsing and metadata and deep property setters and getters
+
+    npm install property-expr
+
+## Use
+
+Setters and getters:
+
+```js
+let expr = require('property-expr')
+let obj = {
+  foo: {
+    bar: ['hi', { buz: { baz: 'found me!' } }]
+  }
+}
+
+let getBaz = expr.getter('foo.bar[1]["buz"].baz')
+let setBaz = expr.setter('foo.bar[1]["buz"].baz')
+
+console.log(getBaz(obj)) // => 'found me!'
+setBaz(obj, 'set me!')
+console.log(obj.foo.bar[1].buz.baz) // => 'set me!'
+```
+
+### `getter(expression, [ safeAccess ])`
+
+Returns a function that accepts an obj and returns the value at the supplied expression. You can create a "safe" getter, which won't error out when accessing properties that don't exist, reducing existance checks befroe property access:
+
+```js
+expr.getter('foo.bar.baz', true)({ foo: {} }) // => undefined
+//instead of val = foo.bar && foo.bar.baz
+```
+
+### `setter(expression)`
+
+Returns a function that accepts an obj and a value and sets the property pointed to by the expression to the supplied value.
+
+### `expr(expression, [ safeAccess], [ paramName = 'data'])`
+
+Returns a normalized expression string pointing to a property on root object
+`paramName`.
+
+    expr.expr("foo['bar'][0].baz", true, 'obj') // => "(((obj.foo || {})['bar'] || {})[0])"
+
+### `split(path) -> Array`
+
+Returns an array of each path segment.
+
+```js
+expr.split("foo['bar'][0].baz") // [ "foo", "'bar'", "0", "baz"]
+```
+
+### `forEach(path, iterator[, thisArg])`
+
+Iterate through a path but segment, with some additional helpful metadata about the segment. The iterator function is called with: `pathSegment`, `isBracket`, `isArray`, `idx`, `segments`
+
+```js
+expr.forEach('foo["bar"][1]', function(
+  pathSegment,
+  isBracket,
+  isArray,
+  idx,
+  segments
+) {
+  // 'foo'   -> isBracket = false, isArray = false, idx = 0
+  // '"bar"' -> isBracket = true,  isArray = false, idx = 1
+  // '0'     -> isBracket = false, isArray = true,  idx = 2
+})
+```
+
+### `normalizePath(path)`
+
+Returns an array of path segments without quotes and spaces.
+
+```js
+expr.normalizePath('foo["bar"][ "1" ][2][ " sss " ]')
+// ['foo', 'bar', '1', '2', ' sss ']
+```
+
+### `new Cache(maxSize)`
+
+Just an utility class, returns an instance of cache. When the max size is exceeded, cache clears its storage.
+
+```js
+var cache = new Cache(2)
+cache.set('a', 123) // returns 123
+cache.get('a') // returns 123
+cache.clear()
+
+cache.set('a', 1)
+cache.set('b', 2) // cache contains 2 values
+cache.set('c', 3) // cache was cleaned automatically and contains 1 value
+```
+
+### CSP
+
+This pacakge used to rely on `new Function` to compile setters and getters into fast
+reusable functions. Since `new Function` is forbidden by folks using Content Security Policy `unsafe-eval`
+we've moved away from that approach. I believe that for most cases the perf hit is not noticable
+but if it is in your case please reach out.
+
+If you really want to use the old version require `property-expr/compiler` instead