Clips empty error in ClipsPy when using make_instance

Question

I am new to CLIPS and to clipsPy. I am trying to create a instance of a CLIPS class

This is the class I have defined and correctly build in my python environment (clipsPy)

ENTITIES_CLASS = """
(defclass ENTITY-CLASS (is-a INITIAL-OBJECT)
 (slot text (type STRING))
 (slot confidence (type FLOAT))
 (slot type (type SYMBOL))
)
"""
env.build(ENTITIES_CLASS)

This works as expected, but when I try to create an instance of this class:

new_instance = "(ent0-0 of ENTITY-CLASS (text 'Bruce Springsteen')(confidence 1.0)(type PER))"
env.make_instance( new_instance )

I get this empty error:

enter image description here

I have tried multiple forms of building the new_instance string but none have work :

new_instance = '(ent0-0 of ENTITY-CLASS (text "Bruce Springsteen")(confidence 1.0)(type PER))'
new_instance = "(ent0-0 of ENTITY-CLASS (text 'Bruce Springsteen') (confidence 1.0) (type PER) )"

Where is my syntax error? I appreciate any help

Answer 1

The empty error issue might be due to how Jupyter re-directs IO.

On IPython I get:

In [1]: import clips 
In [2]: env = clips.Environment() 
In [3]: ENTITIES_CLASS = """ 
 ...: (defclass ENTITY-CLASS (is-a INITIAL-OBJECT) 
 ...: (slot text (type STRING)) 
 ...: (slot confidence (type FLOAT)) 
 ...: (slot type (type SYMBOL)) 
 ...: ) 
 ...: """ 
 ...: env.build(ENTITIES_CLASS) 
In [4]: env.make_instance("(ent0-0 of ENTITY-CLASS (text 'Bruce Springsteen')(confidence 1.0)(type PER))") 
---------------------------------------------------------------------------
CLIPSError Traceback (most recent call last)
<ipython-input-4-92b62ecc6bed> in <module>
----> 1 env.make_instance("(ent0-0 of ENTITY-CLASS (text 'Bruce Springsteen')(confidence 1.0)(type PER))")
/usr/local/lib/python3.6/dist-packages/clips/classes.py in make_instance(self, command)
 215 ist = lib.EnvMakeInstance(self._env, command.encode())
 216 if ist == ffi.NULL:
--> 217 raise CLIPSError(self._env)
 218 
 219 return Instance(self._env, ist)
CLIPSError: [INSFUN7] ('Bruce Springsteen') illegal for single-field slot text of instance [ent0-0] found in put-text primary in class ENTITY-CLASS. [PRCCODE4] Execution halted during the actions of message-handler put-text primary in class ENTITY-CLASS

The problem lies within the way you represent the string 'Bruce Springstreen'. In CLIPS, STRING types are within doublequotes ".

In [4]: env.make_instance('(ent0-0 of ENTITY-CLASS (text "Bruce Springsteen")(confidence 1.0)(type PER))') 
Out[4]: Instance: [ent0-0] of ENTITY-CLASS (text "Bruce Springsteen") (confidence 1.0) (type PER)

• Angel: I am executing < env.make_instance('(ent0-0 of ENTITY-CLASS (text "Bruce Springsteen")(confidence 1.0)(type PER))') > with clips 0.3.3 and python 3.8.6 but I still get the same blank error. Do you know why?
• noxdafox: There's a bug in the old version of CLIPS in which if an error occurs at the API level, the error status is not re-set and any other interaction with CLIPS will still return error. It was fixed in a more recent version of CLIPS. I'll see if I can backport that fix into the CLIPSPy binary.
• Angel: Thank you for your comment, we are using your package in one Uni subject of data science degree, be proud!