# Constant statement

Outputs literal text. Supports escape sequences and optional JSON field formatting when an outname and format are specified. .. summary-end

This statement specifies constant text. It is primarily intended for text-based output so constant fragments, such as newlines, can be included. Example from the testbench:

    template(name="outfmt" type="list") {
        property(name="$!usr!msgnum")
        constant(value="\n")
    }

The following escape sequences are recognized inside the constant text:

- `\\` – single backslash

- `\n` – LF

- `\ooo` – three octal digits representing a character (`\101` is `"A"`). Exactly three digits must be given.

- `\xhh` – two hexadecimal digits representing a character (`\x41` is `"A"`). Exactly two digits must be given.

If an unsupported character follows a backslash, behavior is unpredictable.

When creating structured outputs, constant text without an `outname` parameter is ignored. To include constant data in the name/value tree, provide `outname` as shown:

    template(name="outfmt" type="list") {
        property(name="$!usr!msgnum")
        constant(value="\n" outname="IWantThisInMyDB")
    }

To generate a constant JSON field the `format` parameter can be used:

    template(name="outfmt" type="list" option.jsonf="on") {
              property(outname="message" name="msg" format="jsonf")
              constant(outname="@version" value="1" format="jsonf")
    }

Here the constant statement generates `"@version":"1"`. Both `value` and `format` must be specified.

When you want dotted `outname` values to be emitted as nested objects, enable `option.jsonftree="on"` on the template instead of `option.jsonf`.

## Parameters

- `value` – constant value to emit

- `outname` – output field name for structured outputs

- `format` – empty or `jsonf`

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