dbg()

Output a message in the query response and return the message.

Signature

dbg()(message: Any): Any

Description

The dbg() method outputs message in the query response summary field and returns message. It includes a preview of the calling location.

The message template is:

info: <message>
at *<source>*:<line>:<column>
       |
<line> | dbg(<message>)
       |    ^^^^^^^^^^^
       |

where:

Field Description

<source>

Message source.
One of:

Source Description

query

The dbg() call occurred in the main query body.

udf:<function>

The dbg() call occurred in the user-defined function named <function>

<line>

Line number where dbg() is used.

<column>

Character offset in <line> where dbg() is used.

<message>

String-serialized message.

Parameters

Parameter Type Required Description

message

Any

Yes

Value to output to the query response.

Return value

Type Description

Any

Returns message.

Examples

  1. Output a composed value in the query response:

    Collection.create({
  name: "debug1",
  history_days: dbg(1 + 2 + 3),
})
    {
  name: "debug1",
  coll: Collection,
  ts: Time("2022-12-22T00:24:43.580Z"),
  history_days: 6
} 

Summary:
info: 6
at *query*:3:20
  |
3 |   history_days: dbg(1 + 2 + 3),
  |                    ^^^^^^^^^^^
  |

  2. Output a collection definition object:

    Collection.create(
  dbg({
    name: "debug2",
    history_days: 1 + 2 + 3,
  })
)
    {
  name: "debug2",
  coll: Collection,
  ts: Time("2022-12-22T00:24:43.660Z"),
  history_days: 6
} 

Summary:
info: {name: debug2, history_days: 6}
at *query*:2:6
  |
2 |     dbg({
  |  ______^
3 | |     name: "debug2",
4 | |     history_days: 1 + 2 + 3,
5 | |   })
  | |____^
  |

  3. Output the result of creating a collection:

    dbg(
  Collection.create({
    name: "debug3",
    history_days: 1 + 2 + 3,
  })
)
    {
  name: "debug3",
  coll: Collection,
  ts: Time("2022-12-22T00:24:14.560Z"),
  history_days: 6
} 

Summary:
info: [doc {TODO: render doc fields}]
at *query*:1:4
  |
1 |   dbg(
  |  ____^
2 | |   Collection.create({
3 | |     name: "debug3",
4 | |     history_days: 1 + 2 + 3,
5 | |   })
6 | | )
  | |_^
  |

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