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} } </code></pre> <div class="parameters"> <h3 class="parameters-title">Parameters</h3> <ol> <li><b>newValue</b> <code>{*}</code>: <p>The value set on the property.</p> </li> <li><b>propertyName</b> <code>{String}</code>: <p>The property name being set.</p> </li> </ol> </div> <div class="returns"> <h3 class="returns-title">Returns</h3> <p> <code>{*}</code>: <p>The value that should be passed to <code>set</code> or (if there is no <code>set</code> property) the value to set on the map instance.</p> </p> </div> </div> <div class="signature"> <h2 class="signature-title"> <code>"typeName"</code> </h2> <p>Sets the type to a named type in <a href="can-define.types.html" title="Defines the type, initial value, and get, set, and serialize behavior for an observable property. All type converters leave null and undefined as is except for the "htmlbool" type converter.">types</a>. The default typeName is <code>"observable"</code>.</p> <pre><code class="language-js">age: { type: "number" } </code></pre> <div class="parameters"> <h3 class="parameters-title">Parameters</h3> <ol> <li><b>typeName</b> <code>{String}</code>: <p>A named type in <a href="can-define.types.html" title="Defines the type, initial value, and get, set, and serialize behavior for an observable property. All type converters leave null and undefined as is except for the "htmlbool" type converter.">types</a>.</p> </li> </ol> </div> </div> <div class="signature"> <h2 class="signature-title"> <code>{propDefinition}</code> </h2> <p>A <a href="can-define.types.propDefinition.html" title="Defines the type, initial value, and get, set, and serialize behavior for an observable property. These behaviors can be specified with as an Object, String, Constructor function, Array, a getter expression, or setter expression.">PropDefinition</a> that defines an inline <a href="can-define/map/map.html" title="Create observable objects.">can-define/map/map</a> type. For example:</p> <pre><code class="language-js">address: { type: { street: "string", city: "string" } } </code></pre> </div> <div class="signature"> <h2 class="signature-title"> <code>[Type|propDefinition]</code> </h2> <p>Defines an inline <a href="can-define/list/list.html" title="Create observable lists.">can-define/list/list</a> type that's an array of <code>Type</code> or inline <code>propDefinition</code> <a href="can-define/map/map.html" title="Create observable objects.">can-define/map/map</a> instances. For example:</p> <pre><code class="language-js">people: { type: [Person] }, addresses: { type: [{ street: "string", city: "string" }] } </code></pre> </div> <section class="body"> <h2>Use</h2> <p>The <code>type</code> property specifies the type of the attribute. The type can be specified as either:</p> <ul> <li>A type function that returns the type coerced value.</li> <li>A named type in <a href="can-define.types.html" title="Defines the type, initial value, and get, set, and serialize behavior for an observable property. All type converters leave null and undefined as is except for the "htmlbool" type converter.">types</a>.</li> <li>An object that gets converted into an inline <code>DefineMap</code>.</li> <li>An array that gets converted to an inline <code>DefineList</code>.</li> </ul> <h3>Basic Example</h3> <p>The following example converts the <code>count</code> property to a number and the <code>items</code> property to an array:</p> <pre><code class="language-js">DefineMap.extend({ count: {type: "number"}, items: { type: function(newValue){ if(typeof newValue === "string") { return newValue.split(",") } else if( Array.isArray(newValue) ) { return newValue; } } } }); </code></pre> <p>When a user tries to set those properties like:</p> <pre><code>map.set({count: "4", items: "1,2,3"}); </code></pre> <p>The number converter will be used to turn count into 4, and the items type converter function will be used to turn items into [1,2,3].</p> <h3>Preventing Arrays and Objects from Automatic Conversion</h3> <p>When an array value is set, it is automatically converted into a DefineList. Likewise, objects are converted into DefineMap instances. This behavior can be prevented like the following:</p> <pre><code> locations: {type: "any"} </code></pre> <p>When a user tries to set this property, the resulting value will remain an array.</p> <pre><code>map.locations = [1, 2, 3]; // locations is an array, not a DefineList </code></pre> <h3>Working with the 'compute' type</h3> <p>Setting type as <code>compute</code> allows for resolving a computed property with the .attr() method.</p> <pre><code>MyMap = DefineMap.extend({ value: { type: "compute" } }); var myMap = new MyMap(); var c = compute(5); myMap.value = c; myMap.value //-> 5 c(6); myMap.value //-> 6 //Be sure if setting to pass the new compute var c2 = compute("a"); myMap.value = c2; myMap.value //-> "a" </code></pre> </section> <script type="text/javascript"> var docObject = {"src":{"path":"node_modules/can-define/docs/type.md"},"description":"\nConverts a value set on an instance into an appropriate value.\n","type":"typedef","title":"type","types":[{"type":"function","returns":{"types":[{"type":"undefined"}]},"params":[]},{"type":"string"}],"name":"can-define.types.type","parent":"can-define.behaviors","signatures":[{"code":"type(newValue, propertyName)","description":"\n\nGiven the set value, transform it into a value appropriate to be set.\n`type` is called before [can-define.types.set]. \n\n```js\nage: {\n type: function(newValue, propertyName){\n return +newValue;\n }\n}\n```\n","params":[{"types":[{"type":"*"}],"name":"newValue","description":"The value set on the property."},{"types":[{"type":"String"}],"name":"propertyName","description":"The property name being set.\n"}],"returns":{"types":[{"type":"*"}],"description":"The value that should be passed to `set` or (if there is no `set` property) the value to set on the map instance.\n"}},{"code":"\"typeName\"","description":"\n\nSets the type to a named type in [can-define.types]. 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