Search results
Results From The WOW.Com Content Network
Lookup, find, or get find the value (if any) that is bound to a given key. The argument to this operation is the key, and the value is returned from the operation. If no value is found, some lookup functions raise an exception, while others return a default value (such as zero, null, or a specific value passed to the constructor).
A hash table uses a hash function to compute an index, also called a hash code, into an array of buckets or slots, from which the desired value can be found. During lookup, the key is hashed and the resulting hash indicates where the corresponding value is stored. A map implemented by a hash table is called a hash map.
For a pair of types K, V, the type map[K]V is the type mapping type-K keys to type-V values, though Go Programming Language specification does not give any performance guarantees or implementation requirements for map types. Hash tables are built into the language, with special syntax and built-in functions.
Value range propagation [9] – precompute the potential ranges a calculation could be, allowing for the creation of branch predictions in advance; Sparse conditional constant propagation – range-check some values, allowing tests to predict the most likely branch; Dead-code elimination – remove code that will have no effect on the results
Map functions can be and often are defined in terms of a fold such as foldr, which means one can do a map-fold fusion: foldr f z . map g is equivalent to foldr (f . g) z. The implementation of map above on singly linked lists is not tail-recursive, so it may build up a lot of frames on the stack when called with a large list. Many languages ...
JSON Pointer [10] defines a string syntax for identifying a single value within a given JSON value of known structure. JSONiq [11] is a query and transformation language for JSON. XPath 3.1 [12] is an expression language that allows the processing of values conforming to the XDM [13] data model. The version 3.1 of XPath supports JSON as well as ...
LevelDB is an open-source on-disk key-value store written by Google fellows Jeffrey Dean and Sanjay Ghemawat. [ 2 ] [ 3 ] Inspired by Bigtable , [ 4 ] LevelDB source code is hosted on GitHub under the New BSD License and has been ported to a variety of Unix -based systems, macOS , Windows , and Android .
The ::= rule defines a new algebraic data type, a data type with only data constructors.; The <~ rule defines an interface type - it indicates what properties are characteristic of a person and also gives type constraints on these properties.