Add deprecation guides for ComputedProperties

content/ember/v6/deprecate-import-alias-from-object-computed.md

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+---
+title: Deprecate import alias from @ember/object/computed
+until: 7.0.0
+since: 6.0.0
+---
+
+`alias` from `@ember/object/computed` is deprecated.
+
+It created a second property that reflected another property's value.
+
+## Migration
+Prefer direct access to the original tracked state, or use a simple getter and setter.
+
+Before:
+```js
+import { alias } from '@ember/object/computed';
+import { tracked } from '@glimmer/tracking';
+
+class Person {
+  @tracked firstName = 'Tom';
+  @alias('firstName') name;
+}
+```
+
+After:
+```js
+import { tracked } from '@glimmer/tracking';
+class Person {
+  @tracked firstName = 'Tom';
+  get name() { return this.firstName; }
+  set name(value) { this.firstName = value; }
+}
+```
+If all call sites can use `firstName` directly, remove the alias entirely.

content/ember/v6/deprecate-import-and-from-object-computed.md

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+---
+title: Deprecate import and from @ember/object/computed
+until: 7.0.0
+since: 6.0.0
+---
+
+`and` from `@ember/object/computed` is deprecated. It previously produced the logical AND of dependent keys.
+
+## Migration
+Use a getter with a standard JavaScript boolean expression.
+
+Before:
+```js
+import { and } from '@ember/object/computed';
+class Cart {
+  items = [];
+  user = null;
+  @and('items.length', 'user.isLoggedIn') canCheckout;
+}
+```
+After:
+```js
+class Cart {
+  items = [];
+  user = null;
+  get canCheckout() {
+    return this.items.length > 0 && this.user?.isLoggedIn;
+  }
+}
+```

content/ember/v6/deprecate-import-bool-from-object-computed.md

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+---
+title: Deprecate import bool from @ember/object/computed
+until: 7.0.0
+since: 6.0.0
+---
+
+`bool` from `@ember/object/computed` is deprecated. It coerced the value of another property to a boolean.
+
+## Migration
+Use a getter wrapping `Boolean(...)` or `!!`.
+
+Before:
+```js
+import { bool } from '@ember/object/computed';
+class State {
+  selectedItem = null;
+  @bool('selectedItem') hasSelection;
+}
+```
+
+After:
+```js
+class State {
+  selectedItem = null;
+  get hasSelection() { return Boolean(this.selectedItem); }
+}
+```

content/ember/v6/deprecate-import-computed-property-from-object-computed.md

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+---
+title: Deprecate import ComputedProperty from @ember/object/computed
+until: 7.0.0
+since: 6.0.0
+---
+
+`ComputedProperty` (the default export of `@ember/object/computed`) is deprecated. It was the internal class backing classic computed properties.
+
+## Migration
+Do not construct or refer to `ComputedProperty` directly. Use native getters with `@tracked` state instead.
+
+Before:
+```js
+import ComputedProperty from '@ember/object/computed';
+// rarely used directly
+```
+After: Remove the import; refactor any custom meta-programming to simple getters.
+
+There is no public replacement for the class itself; the concept is removed.

content/ember/v6/deprecate-import-dependent-key-compat-from-object-compat.md

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+---
+title: Deprecate import dependentKeyCompat from @ember/object/compat
+until: 7.0.0
+since: 6.0.0
+---
+
+`dependentKeyCompat` is deprecated. It provided backwards compatibility so tracked getters could participate in classic CP dependency chains.
+
+## Migration
+Remove all ComputedProperties that depend on this getter, then remove `@dependentKeyCompat`.
+
+Before:
+```js
+import { tracked } from '@glimmer/tracking';
+import { computed } from '@ember/object';
+import { dependentKeyCompat } from '@ember/object/compat';
+class Person {
+  @tracked firstName = 'Tom';
+  @tracked lastName = 'Dale';
+  @dependentKeyCompat get givenName() { return this.firstName; }
+  @computed('givenName','lastName') get fullName() { return `${this.givenName} ${this.lastName}`; }
+}
+```
+After:
+```js
+import { tracked } from '@glimmer/tracking';
+class Person {
+  @tracked firstName = 'Tom';
+  @tracked lastName = 'Dale';
+  get givenName() { return this.firstName; }
+  get fullName() { return `${this.givenName} ${this.lastName}`; }
+}
+```

content/ember/v6/deprecate-import-deprecating-alias-from-object-computed.md

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+---
+title: Deprecate import deprecatingAlias from @ember/object/computed
+until: 7.0.0
+since: 6.0.0
+---
+
+`deprecatingAlias` from `@ember/object/computed` is deprecated. It created an alias that emitted a deprecation when accessed.
+
+## Migration
+Remove the indirection and update callers to reference the canonical property. If you still need a deprecation message temporarily, implement a manual getter that logs once.
+
+Before (framework provided deprecation):
+```js
+import { deprecatingAlias } from '@ember/object/computed';
+class Person {
+  firstName = 'Tom';
+  @deprecatingAlias('firstName', { id: 'app.old-name', until: '7.0.0' }) givenName;
+}
+```
+After (direct access):
+```js
+class Person {
+  firstName = 'Tom';
+}
+```
+Optional transitional getter:
+```js
+import { deprecate } from '@ember/debug';
+class Person {
+  firstName = 'Tom';
+  get givenName() {
+    deprecate('Usage of `givenName` is deprecated, use `firstNAme` instead.');
+    return this.firstName;
+  }
+}
+```

content/ember/v6/deprecate-import-empty-from-object-computed.md

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+---
+title: Deprecate import empty from @ember/object/computed
+until: 7.0.0
+since: 6.0.0
+---
+
+`empty` from `@ember/object/computed` is deprecated. It returned true when the dependent value was `null`, `undefined`, an empty string, or had length 0.
+
+## Migration
+Implement the check in a getter.
+
+Before:
+```js
+import { empty } from '@ember/object/computed';
+class ListState {
+  items = [];
+  @empty('items') isEmpty;
+}
+```
+After:
+```js
+import { isEmpty } from '@ember/utils';
+class ListState {
+  items = [];
+  get isEmpty() { return isEmpty(this.items); }
+}
+```
+Combine with `!` for `notEmpty` replacement.

content/ember/v6/deprecate-import-equal-from-object-computed.md

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+---
+title: Deprecate import equal from @ember/object/computed
+until: 7.0.0
+since: 6.0.0
+---
+
+`equal` from `@ember/object/computed` is deprecated. It compared a dependent key's value to a constant.
+
+## Migration
+Use a getter with a strict equality expression.
+
+Before:
+```js
+import { equal } from '@ember/object/computed';
+class Person {
+  role = 'admin';
+  @equal('role', 'admin') isAdmin;
+}
+```
+
+After:
+```js
+class Person {
+  role = 'admin';
+  get isAdmin() {
+    return this.role === 'admin';
+  }
+}
+```

content/ember/v6/deprecate-import-expand-properties-from-object-computed.md

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+---
+title: Deprecate import expandProperties from @ember/object/computed
+until: 7.0.0
+since: 6.0.0
+---
+
+`expandProperties` is deprecated. It expanded bracket / brace notation in classic CP dependent key strings.
+
+## Migration
+This is largely unneeded and there is no direct replacement.
+
+Before:
+```js
+import { expandProperties } from '@ember/object/computed';
+expandProperties('user.{first,last}Name', (prop) => {/* ... */});
+```
+
+After: List properties explicitly: `user.firstName`, `user.lastName`.

content/ember/v6/deprecate-import-gt-from-object-computed.md

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+---
+title: Deprecate import gt from @ember/object/computed
+until: 7.0.0
+since: 6.0.0
+---
+
+`gt` (greater than) from `@ember/object/computed` is deprecated.
+
+## Migration
+Use a comparison inside a getter.
+
+Before:
+```js
+import { gt } from '@ember/object/computed';
+class Score {
+  value = 42;
+  @gt('value', 10) isHigh;
+}
+```
+
+After:
+```js
+class Score {
+  value = 42;
+  get isHigh() {
+    return this.value > 10;
+  }
+}
+```

content/ember/v6/deprecate-import-gte-from-object-computed.md

@@ -0,0 +1,26 @@
+---
+title: Deprecate import gte from @ember/object/computed
+until: 7.0.0
+since: 6.0.0
+---
+
+`gte` (greater than or equal) from `@ember/object/computed` is deprecated.
+
+Before:
+```js
+import { gte } from '@ember/object/computed';
+class Score {
+  value = 42;
+  @gte('value', 10) meetsThreshold;
+}
+```
+
+After:
+```js
+class Score {
+  value = 42;
+  get meetsThreshold() {
+    return this.value >= 10;
+  }
+}
+```

content/ember/v6/deprecate-import-lt-from-object-computed.md

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+---
+title: Deprecate import lt from @ember/object/computed
+until: 7.0.0
+since: 6.0.0
+---
+
+`lt` (less than) from `@ember/object/computed` is deprecated.
+
+Before:
+```js
+import { lt } from '@ember/object/computed';
+class Score {
+  value = 5;
+  @lt('value', 10) isLow;
+}
+```
+
+After:
+```js
+class Score {
+  value = 5;
+  get isLow() {
+    return this.value < 10;
+  }
+}
+```

content/ember/v6/deprecate-import-lte-from-object-computed.md

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+---
+title: Deprecate import lte from @ember/object/computed
+until: 7.0.0
+since: 6.0.0
+---
+
+`lte` (less than or equal) from `@ember/object/computed` is deprecated.
+
+Before:
+```js
+import { lte } from '@ember/object/computed';
+class Score {
+  value = 5;
+  @lte('value', 10) withinLimit;
+}
+```
+
+After:
+```js
+class Score {
+  value = 5;
+  get withinLimit() {
+    return this.value <= 10;
+  }
+}
+```