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In computing science and informatics, nesting is where information is organized in layers, or where objects contain other similar objects. It almost always refers to self-similar or recursive structures in some sense. Nesting can mean: * nested calls: * * using several levels of subroutines * * recursive calls * nested levels of parentheses in arithmetic expressions * nested blocks of imperative source code such as nested if-clauses, while-clauses, repeat-until clauses etc. * information hiding: * * nested function definitions with lexical scope * * nested data structures such as records, objects, classes, etc. * nested virtualization, also called recursive virtualization: running a virtual machine inside another virtual machine ==In spreadsheets== In a spreadsheet functions can be ''nested'' one into another, making complex formulas. The function wizard of the OpenOffice.org Calc application allows to navigate through multiple levels of nesting, letting the user to edit (and possibly correct) each one of them separately. Naturally, to allow the mathematical resolution of these chained (or better: ''nested'') formulas, the inner expressions must be previously evaluated, and this outward direction is essential because the results that the ''internal'' functions return are temporarily used as entry data for the ''external'' ones. Due to the potential accumulation of parentheses in only one code line, editing and error detecting (or debugging) can became somehow ''awkward''. That is why modern programming environments -as well as spreadsheet programs- highlight in bold type the pair corresponding to the current editing position. The (automatic) balancing control of the opening and closing parenthesis known as ''brace match checking''. 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Nesting (computing)」の詳細全文を読む スポンサード リンク
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