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| <h3>Expressions</h3> |
| <p>An <b>expression</b> is a snippet of code that can be evaluated to produce a |
| value. The context for an expression depends on the particular debug |
| model. Some expressions may need to be evaluated at a specific location in |
| the program so that its variables can be referenced. |
| <a href="../reference/api/org/eclipse/debug/core/model/IExpression.html"><b>IExpression</b></a> |
| defines a general interface for debug expressions.</p> |
| <p>An expression manager (<a href="../reference/api/org/eclipse/debug/core/IExpressionManager.html"><b>IExpressionManager</b></a>) |
| keeps track of all of the expressions in the workspace. It will also fire |
| events to interested listeners as expressions are added, removed, or changed.</p> |
| <p>Expressions can be used to implement "inspectors," or "scrapbooks" that let users evaluate |
| code snippets. The Java tooling uses expressions to implement the |
| expression generated when the user inspects the source code.</p> |
| <p>A <b>watch expression</b> is an expression that is repeatedly evaluated as the program executes. |
| <a href="../reference/api/org/eclipse/debug/core/model/IWatchExpression.html"><b>IWatchExpression</b></a> |
| defines a specialized kind of <a href="../reference/api/org/eclipse/debug/core/model/IExpression.html"><b>IExpression</b></a> |
| that updates the value of the expression when supplied with a new debug context. Watch expressions are used to implement |
| "watch lists," which show changes in the value of an expression as the program executes.</p> |
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