MediaWiki API result

{
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    "continue": {
        "gapcontinue": "ReadRecords_(Dataset_function)",
        "continue": "gapcontinue||"
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    "warnings": {
        "main": {
            "*": "Subscribe to the mediawiki-api-announce mailing list at <https://lists.wikimedia.org/postorius/lists/mediawiki-api-announce.lists.wikimedia.org/> for notice of API deprecations and breaking changes."
        },
        "revisions": {
            "*": "Because \"rvslots\" was not specified, a legacy format has been used for the output. This format is deprecated, and in the future the new format will always be used."
        }
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    "query": {
        "pages": {
            "5013": {
                "pageid": 5013,
                "ns": 0,
                "title": "ReadBlock (Dataset function)",
                "revisions": [
                    {
                        "contentformat": "text/x-wiki",
                        "contentmodel": "wikitext",
                        "*": "{{Template:Dataset:ReadBlock subtitle}}\n\nThis function reads a block of data from an input <var>Dataset</var>.\n==Syntax==\n{{Template:Dataset:ReadBlock syntax}}\n===Syntax terms===\n<table class=\"syntaxTable\">\n<tr><th>%string</th>\n<td>A [[Longstrings|longstring]] variable (though for small blocks, a regular string variable might suffice) to receive the block of data.\n</td></tr>\n<tr><th>dataset</th>\n<td>A reference to an instance of a <var>Dataset</var> object.\n \n</td></tr></table>\n==Usage notes==\n<ul>\n<li>The <var>Dataset</var> object must be an input object, that is, its\n<var>[[Output (Dataset property)|Output]]</var> property must be <var>False</var>, to use the <var>ReadBlock</var> method.\nUsing <var>ReadBlock</var> against an output dataset results in request cancellation.\n\n<li>The <var>Dataset</var> object must be in the <var>Open</var> [[Dataset class#The DatasetState enumeration|state]] to use the <var>ReadBlock</var> method.\nUsing <var>ReadBlock</var> against a <var>Dataset</var> in the <var>Closed</var> or <var>AfterEnd</var> state\nresults in request cancellation.\n\n<li>If a <var>ReadBlock</var> method is used after a <var>[[ReadRecord (Dataset function)|ReadRecord]]</var> method.\nany records in the block after the record returned by the preceding <var>ReadRecord</var> are skipped.\nAs such, it is generally not a good idea to mix <var>ReadBlock</var> and <var>ReadRecord</var>\nprocessing for a single dataset.\n\n<li>For F or FB files, the string returned by <var>ReadBlock</var> has a length that\nis an exact multiple of the <var>[[RecordLength (Dataset property)|RecordLength]]</var> property value.\n\n<li>For V or VB files, the string returned by <var>ReadBlock</var> has a binary BDW\n(Block Descriptor Word), and the individual records will be preceded by a binary RDW (Record Descriptor Word).\nThis is true even under CMS, where records are not really stored on disks\nwith BDWs and RDWs &mdash; they are mapped to the MVS format by BSAM\nsimulation.\n\n<li>Given the difficulty of working with blocked data, especially for V and\nVB format datasets, it is generally a better idea to use <var>ReadRecord</var> than\n<var>ReadBlock</var>, and have the <var>Dataset</var> class handle the physical data formats.\n\n<li>When a <var>ReadBlock</var> reaches the end of a file, it returns a null string and\nswitches the dataset to the <var>AfterEnd</var> state.\nAfter this, a <var>ReadRecord</var> or <var>ReadBlock</var> results in request cancellation.\n<var>ReadBlock</var> will never return a null string except at end of file.\n</ul>\n\n==See also==\n{{Template:Dataset:ReadBlock footer}}"
                    }
                ]
            },
            "5014": {
                "pageid": 5014,
                "ns": 0,
                "title": "ReadRecord (Dataset function)",
                "revisions": [
                    {
                        "contentformat": "text/x-wiki",
                        "contentmodel": "wikitext",
                        "*": "{{Template:Dataset:ReadRecord subtitle}}\n\n==Syntax==\n{{Template:Dataset:ReadRecord syntax}}\n===Syntax terms===\n<table class=\"syntaxTable\">\n<tr><th>%string</th>\n<td>A string or [[Longstrings|longstring]] variable to receive the block of data.\n</td></tr>\n<tr><th>dataset</th>\n<td>A reference to an instance of a <var>Dataset</var> object.\n \n</td></tr></table>\n==Usage notes==\n<ul>\n<li>The <var>Dataset</var> object must be an input object, that is, its\n<var>[[Output (Dataset property)|Output]]</var> property must be <var>False</var> to use the <var>ReadRecord</var> method.\nUsing <var>ReadRecord</var> against an output dataset results in request cancellation.\n\n<li>The <var>Dataset</var> object must be in the <var>Open</var> [[Dataset class#The DatasetState enumeration|state]] to use the <var>ReadRecord</var> method.\nUsing <var>ReadRecord</var> against a dataset in the <var>Closed</var> or <var>AfterEnd</var> state\nresults in request cancellation.\n\n<li>If a <var>ReadRecord</var> method is used after a <var>ReadBlock</var> method, the first record\nin the block after the block returned by the <var>ReadBlock</var> is returned.\n\n<li>For F or FB files, the string returned by <var>ReadRecord</var> has a length that\nis exactly equal to the <var>RecordLength</var>.\n\n<li>For V or VB files, the string returned by <var>ReadRecord</var> has a length less\nthan the <var>[[RecordLength (Dataset property)|RecordLength]]</var> property value.\nIt does '''not''' contain the record's RDW, that is, it only contains the\ndata portion of the record.\nAs such, a program that uses <var>ReadRecord</var> can generally be used without\nmodification (except for, perhaps, record padding issues) for different\n<var>RecordFormats</var>.\n\n<li>When a <var>ReadRecord</var> reaches the end of a file, it returns a null string and\nswitches the dataset to the <var>AfterEnd</var> state.\nAfter this, a <var>ReadRecord</var> or <var>ReadBlock</var> results in request cancellation.\nFor V or VB datasets, it is possible for <var>ReadRecord</var> to return a null record\nwhen it is not at the end of file.\nBecause of this, it is probably best to check the <var>Dataset</var>'s\n<var>[[State (Dataset property)|State]]</var> property rather than using the size of the returned\nrecord to determine if the end of file has been reached.\n</ul>\n\n==Example==\nFor a simple example, see [[Dataset class#Dataset example|\"Dataset example\"]].\n\n==See also==\n{{Template:Dataset:ReadRecord footer}}"
                    }
                ]
            }
        }
    }
}