- pengines:event_to_json(+Event, -JSON, +Format, +VarNames) is semidet[private]
- Provide additional translations for Prolog terms to output.
Defines formats are:
- 'json-s'
- Simple or string format: Prolog terms are sent using quoted write.
- 'json-html'
- Serialize responses as HTML string. This is intended for
applications that emulate the Prolog toplevel. This format
carries the following data:
- data
- List if answers, where each answer is an object with
- variables
- Array of objects, each describing a variable. These
objects contain these fields:
- variables: Array of strings holding variable names
- value: HTML-ified value of the variables
- substitutions: Array of objects for substitutions
that break cycles holding:
- var: Name of the inserted variable
- value: HTML-ified value
- residuals
- Array of strings representing HTML-ified residual goals.
- pengines:event_to_json(+PrologEvent, -JSONEvent, +Format, +VarNames)[private]
- If Format equals
'json-s'or'json-html', emit a simplified JSON representation of the data, suitable for notably SWISH. This deals with Prolog answers and output messages. If a message originates from print_message/3, it gets several additional properties:- message:Kind
- Indicate the kind of the message (
error,warning, etc.) - location:_41316{ch:CharPos, file:File, line:Line}
- If the message is related to a source location, indicate the file and line and, if available, the character location.
- pengines:event_to_json(+Event, -JSON, +Format, +VarNames)[private]
- Implement translation of a Pengine event to
json-htmlformat. This format represents the answer as JSON, but the variable bindings are (structured) HTML strings rather than JSON objects.CHR residual goals are not bound to the projection variables. We hacked a bypass to fetch these by returning them in a variable named _residuals, which must be bound to a term '$residuals'(List). Such a variable is removed from the projection and added to residual goals.