# Copyright 2005-2007 Kevin Reid, under the terms of the MIT X license
# found at http://www.opensource.org/licenses/mit-license.html ................

  ? def <qu> := <import:org.quasiliteral.*>; null


  ? def makeAstroTag := <qu:astro.makeAstroTag>
  # value: <makeAstroTag>
  
  ? def tag := makeAstroTag(44, "foo", nullOk)
  # value: <foo>

  ? tag == makeAstroTag(44, "foo", nullOk)
  # value: true

  ? tag != makeAstroTag(null, "foo", nullOk)
  # value: true
  
  ? [tag.getOptTagCode(), tag.getTagName(), tag.getDataGuard()]
  # value: [44, "foo", nullOk]

XXX EoJ tags respond to isTagForData/1, op__cmp/1

  ? def makeTerm := <qu:term.makeTerm>
  # value: <makeTerm>

  ? makeTerm(tag, 99, null, [])
  # problem: must be null
  
  ? def term := makeTerm(tag, null, null, [])
  # value: term`foo`

  ? def nestedTerm := makeTerm(makeAstroTag(null, "bar", nullOk), null, null, [term])
  # value: term`bar(foo)`

Term guard

  ? def Term := makeTerm.asType()
  # value: Term
  
  ? Term == <type:org.quasiliteral.term.Term>
  # value: true
  
 Basic accept/reject

  ? "foo" :Term
  # problem: not a Term: "foo"
  
  ? term :Term
  # value: term`foo`

 Terms can hold arbitrary data, but are not 'standard' Terms

  ? def termBadData := makeTerm(makeAstroTag(44, "bar", any), def x {}, null, [])
  # value: term`bar<x>`
  
  ? termBadData :Term
  # problem: doesn't match any of [nullOk, int, float64, char, Twine]

 Terms can hold arbitrary children, but ditto.
  
  ? def termNonTree := makeTerm(tag, null, null, ["bar"]) 
  # value: term`foo("bar")`
  
  ? termNonTree :Term
  # problem: not a Term: "bar"
  
  ? def LooseTerm := Term[any, any, any]
  # value: Term[any, any, any]
  
  ? termNonTree :LooseTerm
  # value: term`foo("bar")`
  
  ? termBadData :LooseTerm
  # value: term`bar<x>`

XXX test tag restrictions

  ? term.getTerms()
  # value: [term`foo`]
  
  ? makeTerm(tag, null, null, [term]).withoutArgs()
  # value: term`foo`