docs: remove outdated expressions documentation and update navigation (#4287)

Co-authored-by: cubic-dev-ai[bot] <191113872+cubic-dev-ai[bot]@users.noreply.github.com>

archive/deleted-redirects

@@ -128,7 +128,6 @@
 /code-examples/javascript-functions/get-binary-data-buffer/   /code/cookbook/code-node/get-binary-data-buffer/  301
 /code-examples/javascript-functions/console-log/   /code/cookbook/code-node/console-log/  301
 /code-examples/ai-code/   /code/ai-code/  301
-/code-examples/expressions/check-incoming-data/   /code/cookbook/expressions/check-incoming-data/  301
 /code-examples/expressions/   /code/expressions/  301
 /code-examples/expressions/expressions/   /code/expressions/  301
 /code-examples/javascript-functions/   /code/code-node/  301

docs/_redirects

@@ -192,7 +192,6 @@
 /code-examples/javascript-functions/get-binary-data-buffer/   /code/cookbook/code-node/get-binary-data-buffer/  301
 /code-examples/javascript-functions/console-log/   /code/cookbook/code-node/console-log/  301
 /code-examples/ai-code/   /code/ai-code/  301
-/code-examples/expressions/check-incoming-data/   /code/cookbook/expressions/check-incoming-data/  301
 /code-examples/expressions/   /code/expressions/  301
 /code-examples/expressions/expressions/   /code/expressions/  301
 /code-examples/javascript-functions/   /code/code-node/  301

docs/code/cookbook/expressions/check-incoming-data.md

@@ -1,22 +0,0 @@
----
-contentType: howto
----
-
-# Check incoming data
-
-At times, you may want to check the incoming data. If the incoming data doesn't match a condition, you may want to return a different value. For example, you want to check if a variable from the previous node is empty and return a string if it's empty. Use the following code snippet to return `not found` if the variable is empty.
-
-```javascript
-{{$json["variable_name"]? $json["variable_name"] :"not found"}}
-```
-
-The above expression uses the ternary operator. You can learn more about the ternary operator [here](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Operators/Conditional_Operator).
-
-As an alternative, you can use the [nullish coalescing operator (??)](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Operators/Nullish_coalescing) or the [logical or operator (||)](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Operators/Logical_OR):
-
-```javascript
-{{ $x ?? "default value" }}
-{{ $x || "default value" }}
-```
-
-In either of the above two cases, the value of `$x` will be used if it's set to a non-null, non-false value. The string `default value` is the fallback value.

docs/code/cookbook/expressions/common-issues.md

@@ -1,59 +0,0 @@
----
-title: Expressions common issues
-description: Documentation for common issues and questions related to expressions in n8n, a workflow automation platform. Includes details of the issue and suggested solutions.
-contentType: howto
----
-
-# Expressions common issues
-
-Here are some common errors and issues related to [expressions](/data/expressions.md) and steps to resolve or troubleshoot them.
-
-## The 'JSON Output' in item 0 contains invalid JSON
-
-This error occurs when you use JSON mode but don't provide a valid JSON object. Depending on the problem with the JSON object, the error sometimes display as `The 'JSON Output' in item 0 does not contain a valid JSON object`.
-
-To resolve this, make sure that the code you provide is valid JSON:
-
-- Check the JSON with a [JSON validator](https://jsonlint.com/).
-- Check that your JSON object doesn't reference undefined input data. This may occur if the incoming data doesn't always include the same fields.
-
-## Can't get data for expression
-
-This error occurs when n8n can't retrieve the data referenced by an expression. Often, this happens when the preceding node hasn't been run yet.
-
-Another variation of this may appear as `Referenced node is unexecuted`.  In that case, the full text of this error will tell you the exact node that isn't executing in this format:
-
-> An expression references the node '<node-name>', but it hasn’t been executed yet. Either change the expression, or re-wire your workflow to make sure that node executes first.
-> 
-
-To begin troubleshooting, test the workflow up to the named node.
-
-For nodes that use JavaScript or other custom code, you can check if a previous node has executed before trying to use its value by checking the following:
-
-```javascript
-$("<node-name>").isExecuted
-```
-
-As an example, this JSON references the parameters of the input data. This error will display if you test this step without connecting it to another node:
-
-```javascript
-{
-  "my_field_1": {{ $input.params }}
-}
-```
-
-## Invalid syntax
-
-This error occurs when you use an expression that has a syntax error.
-
-For example, the expression in this JSON includes a trailing period, which results in an invalid syntax error:
-
-```jsx
-{
-  "my_field_1": "value",
-  "my_field_2": {{ $('If').item.json. }}
-}
-
-```
-
-To resolve this error, check your [expression syntax](/data/expressions.md) to make sure they follow the expected format.

docs/code/cookbook/expressions/index.md

@@ -1,20 +0,0 @@
----
-description: Code examples you can use in expressions.
-contentType: overview
----
-
-# Expressions cookbook
-
-This section contains examples and recipes for tasks you can do with [expressions](/glossary.md#expression-n8n).
-
-/// note | Python support
-You can use Python in the Code node. It isn't available in expressions.
-///
-[[% import "_macros/section-toc.html" as sectionToc %]]
-
-[[ sectionToc.sectionToc(page) ]]
-
-## Related resources
-
-* [Built-in methods and variables reference](/code/builtin/overview.md)
-* [Expressions](/data/expressions.md)

docs/data/expressions-for-transformation.md

@@ -84,3 +84,55 @@ The following code use the Luxon date and time library to find the time between
   return diffInMonths.toObject();
 })()}}
 ```
+
+## Common issues
+
+Here are some common errors and issues related to [expressions](/data/expressions.md) and steps to resolve or troubleshoot them.
+
+### The 'JSON Output' in item 0 contains invalid JSON
+
+This error occurs when you use JSON mode but don't provide a valid JSON object. Depending on the problem with the JSON object, the error sometimes displays as `The 'JSON Output' in item 0 does not contain a valid JSON object`.
+
+To resolve this, make sure that the code you provide is valid JSON:
+
+- Check the JSON with a [JSON validator](https://jsonlint.com/).
+- Check that your JSON object doesn't reference undefined input data. This may occur if the incoming data doesn't always include the same fields.
+
+### Can't get data for expression
+
+This error occurs when n8n can't retrieve the data referenced by an expression. Often, this happens when the preceding node hasn't been run yet.
+
+Another variation of this may appear as `Referenced node is unexecuted`.  In that case, the full text of this error will tell you the exact node that isn't executing in this format:
+
+> An expression references the node '<node-name>', but it hasn't been executed yet. Either change the expression, or re-wire your workflow to make sure that node executes first.
+
+To begin troubleshooting, test the workflow up to the named node.
+
+For nodes that use JavaScript or other custom code, you can check if a previous node has executed before trying to use its value by checking the following:
+
+```javascript
+$("<node-name>").isExecuted
+```
+
+As an example, this JSON references the parameters of the input data. This error will display if you test this step without connecting it to another node:
+
+```javascript
+{
+  "my_field_1": {{ $input.params }}
+}
+```
+
+### Invalid syntax
+
+This error occurs when you use an expression that has a syntax error.
+
+For example, the expression in this JSON includes a trailing period, which results in an invalid syntax error:
+
+```jsx
+{
+  "my_field_1": "value",
+  "my_field_2": {{ $('If').item.json. }}
+}
+```
+
+To resolve this error, check your [expression syntax](/data/expressions.md) to make sure it follows the expected format.

docs/integrations/builtin/app-nodes/n8n-nodes-base.notion/common-issues.md

@@ -70,4 +70,4 @@ To work around this, check for the existence of the field data before sending it
 
 To check for the data before executing the Notion node, use an [If](/integrations/builtin/core-nodes/n8n-nodes-base.if.md) node to check whether the field is unset. This allows you to use the [Edit Fields (Set)](/integrations/builtin/core-nodes/n8n-nodes-base.set.md) node to conditionally remove the field when it doesn't have a valid value.
 
-As an alternative, you can set a [default value](/code/cookbook/expressions/check-incoming-data.md) if the incoming data doesn't provide one.
+As an alternative, you can set a default value if the incoming data doesn't provide one.

docs/integrations/builtin/app-nodes/n8n-nodes-base.whatsapp/common-issues.md

@@ -15,7 +15,7 @@ This error occurs when WhatsApp Business Cloud rejects your request because of a
 
 To resolve this issue, review the parameters in your [message template](https://www.facebook.com/business/help/2055875911147364?id=2129163877102343). Pay attention to each parameter's data type and the order they're defined in the template.
 
-Check the data that n8n is mapping to the template parameters. If you're using expressions to set parameter values, check the input data to make sure each item resolves to a valid value. You may want to use the [Edit Fields (Set) node](/integrations/builtin/core-nodes/n8n-nodes-base.set.md) or [set a fallback value](/code/cookbook/expressions/check-incoming-data.md) to ensure you send a value with the correct format.
+Check the data that n8n is mapping to the template parameters. If you're using expressions to set parameter values, check the input data to make sure each item resolves to a valid value. You may want to use the [Edit Fields (Set) node](/integrations/builtin/core-nodes/n8n-nodes-base.set.md) or set a fallback value to ensure you send a value with the correct format.
 
 ## Working with non-text media
 

nav.yml

@@ -1314,10 +1314,6 @@ nav:
               - getWorkflowStaticData: code/cookbook/builtin/get-workflow-static-data.md
               - (node-name).all: code/cookbook/builtin/all.md
               - vars: code/cookbook/builtin/vars.md
-          - Expressions:
-              - code/cookbook/expressions/index.md
-              - Check incoming data: code/cookbook/expressions/check-incoming-data.md
-              - Common issues:  code/cookbook/expressions/common-issues.md
           - Code node:
               - code/cookbook/code-node/index.md
               - Get number of items returned by last node: code/cookbook/code-node/number-items-last-node.md