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"typeDescriptions": { "typeIdentifier": "t_uint256", "typeString": "uint256" } }, "id": 316, "nodeType": "ExpressionStatement", "src": "1338:38:4" } ] }, "documentation": null, "id": 318, "implemented": true, "kind": "function", "modifiers": [], "name": "decrement", "nodeType": "FunctionDefinition", "parameters": { "id": 305, "nodeType": "ParameterList", "parameters": [ { "constant": false, "id": 304, "name": "counter", "nodeType": "VariableDeclaration", "scope": 318, "src": "1294:23:4", "stateVariable": false, "storageLocation": "storage", "typeDescriptions": { "typeIdentifier": "t_struct$_Counter_$279_storage_ptr", "typeString": "struct Counters.Counter" }, "typeName": { "contractScope": null, "id": 303, "name": "Counter", "nodeType": "UserDefinedTypeName", "referencedDeclaration": 279, "src": "1294:7:4", "typeDescriptions": { "typeIdentifier": "t_struct$_Counter_$279_storage_ptr", "typeString": "struct Counters.Counter" } }, "value": null, "visibility": "internal" } ], "src": "1293:25:4" }, "returnParameters": { "id": 306, "nodeType": "ParameterList", "parameters": [], "src": "1328:0:4" }, "scope": 319, "src": "1275:108:4", "stateMutability": "nonpayable", "superFunction": null, "visibility": "internal" } ], "scope": 320, "src": "626:759:4" } ], "src": "0:1386:4" }, "compiler": { "name": "solc", "version": "0.5.2+commit.1df8f40c.Emscripten.clang" }, "networks": {}, "schemaVersion": "3.0.16", "updatedAt": "2019-10-19T07:38:02.310Z", "devdoc": { "author": "Matt Condon (@shrugs)", "details": "Provides counters that can only be incremented or decremented by one. This can be used e.g. to track the number of elements in a mapping, issuing ERC721 ids, or counting request ids * Include with `using Counters for Counters.Counter;` Since it is not possible to overflow a 256 bit integer with increments of one, `increment` can skip the SafeMath overflow check, thereby saving gas. This does assume however correct usage, in that the underlying `_value` is never directly accessed.", "methods": {}, "title": "Counters" }, "userdoc": { "methods": {} } }