[log.error]

log.error is a slot in the log namespace, in Hyperlambda, the language of Magic Cloud. Writes an error-level log entry; use for caught exceptions or failed operations that need follow-up.

• Value (log-message,text), required: Log message to write
• Returns: Id of the log entry created, or null if the configured log level filtered it out

Arguments

Required arguments come first, then the optional ones in the order they are declared.

Argument	Type	Required	Description
any node name	string	no	Metadata entry stored with the log item when the slot has an input value; otherwise evaluated content fragment. Can be repeated.
[exception]	string	no	Exception text attached to error and fatal log entries.

Guide

How to use log.error

JSON declaration

This is the complete declaration of log.error, as the running system describes it. It is also published as slot.json.

JSON declaration

{
  "name": "log.error",
  "description": "Writes an error-level log entry; use for caught exceptions or failed operations that need follow-up",
  "signature": {
    "input": {
      "kind": "log-message,text",
      "description": "Log message to write",
      "required": true,
      "mode": "ValueOrExpression"
    },
    "children": {
      "*": {
        "type": "string",
        "kind": "log-metadata",
        "description": "Metadata entry stored with the log item when the slot has an input value; otherwise evaluated content fragment",
        "required": false,
        "mode": "ValueOrExpression",
        "cardinality": "ZeroOrMore",
        "role": "DynamicMap",
        "evaluation": "EvalSelf",
        "projection": "Value"
      },
      "exception": {
        "type": "string",
        "kind": "exception-text",
        "description": "Exception text attached to error and fatal log entries",
        "required": false,
        "mode": "ValueOrExpression",
        "cardinality": "ZeroOrOne",
        "role": "Option",
        "projection": "Value"
      }
    },
    "output": {
      "mode": "Value",
      "kind": "log-entry-id",
      "description": "Id of the log entry created, or null if the configured log level filtered it out"
    }
  }
}

---

← log.debug

all log.* slots

log.fatal →