FV: Unable to use (fold) in @model Property Definitions

[chicodias]

Issue Description

The fold function fails to parse when used within a @model property definition in Pact, as demonstrated in the module A below. Replacing fold with and logical operators in module B works as expected. Documentation for fold usage can be found here.

Steps to Reproduce

Failing Scenario: Module A with fold

1. Code:

   (module A G
    @model
    [
      (defproperty test-prop
        (cond1:bool cond2:bool cond3:bool)
        (fold (and) true [cond1 cond2 cond3])
      )
    ]
   
    (defcap G() true)
   
    (defun T(v1:bool v2:bool v3:bool)
      @model [ (property (test-prop v1 v2 v3))]
      true)
   )
   
   (verify "A")

2. Verification Output:

   "Verification of A failed"
   :OutputFailure: test.pact:20:23: could not parse (test-prop v1 v2 v3): in (fold (and) true [cond1,cond2,cond3]), couldn't find property named fold

Working Scenario: Module B with and

1. Code:

   (module B G
    @model
    [
      (defproperty test-prop
        (cond1:bool cond2:bool cond3:bool)
        (and (and cond1 cond2) cond3)
      )
    ]
   
    (defcap G() true)
   
    (defun T(v1:bool v2:bool v3:bool)
      @model [ (property (test-prop v1 v2 v3))]
      true)
   )
   
   (verify "B")

2. Verification Output:

   "Verification of B succeeded"
   test2.pact:18:23:OutputFailure: Invalidating model found in B.T
    Program trace:
      entering function B.T with arguments
        v1 = False
        v2 = False
        v3 = False
   
        returning with False

Expected Behavior

The fold function should be parsed correctly and utilized in property definitions within @model blocks, as per its documentation.

Actual Behavior

The use of fold results in a parsing error during the verification process, whereas using nested and operators does not cause any parsing issues and behaves as expected.

Debug Information

• Pact Version: 4.11