Fix semantics of print statement & implement output in vanilla ACT-R

The print statement was using plain ids but we weren't determining if they were vars or not. It makes more sense and reads better to require vars with "?".

This also addresses #32 (output) for vanilla ACT-R.

README.md

@@ -312,7 +312,7 @@ increment {
         retrieval `count( ?x ?next )`
     }
     do {
-        print x
+        print ?x
         recall `count( ?next ? )`
         set start of goal to next
     }
@@ -323,7 +323,7 @@ stop {
         goal `countFrom( ?x ?x counting )`
     }
     do {
-        print x
+        print ?x
         clear goal
     }
 }
@@ -357,11 +357,11 @@ The _do_ section in the productions uses a small language which currently unders
 | command                                                               | example                         |
 | --------------------------------------------------------------------- | ------------------------------- |
 | clear _(buffer name)+_                                                | clear goal, retrieval           |
-| print _(string or ident or number)+_                                  | print foo, 'text', 42           |
+| print _(string or var or number)+_                                    | print 'text', ?var, 42          |
 | recall _(pattern)_                                                    | recall \`car( ?colour )\`       |
 | set _(slot name)_ of _(buffer name)_ to _(string or ident or number)_ | set sum of goal to 6            |
 | set _(buffer name)_ to _(pattern)_                                    | set goal to \`start( 6 None )\` |
-| write _(string or ident or number)+_ to _(text output name)_          | write 'foo' to text             |
+| write _(string or var or number)+_ to _(text output name)_            | write 'text', ?var to text      |
 
 ## Processing
 

actr/production.go

@@ -29,9 +29,17 @@ type ClearStatement struct {
 	BufferNames []string
 }
 
+// Value holds something that may be printed.
+type Value struct {
+	Var    *string
+	ID     *string
+	Str    *string
+	Number *float64
+}
+
 // PrintStatement outputs the string, id, or number to stdout.
 type PrintStatement struct {
-	Args []string // the strings, identifiers, or numbers to print
+	Values *[]*Value
 }
 
 // RecallStatement is used to pull information from a memory.
@@ -42,7 +50,7 @@ type RecallStatement struct {
 
 // WriteStatement will send the list of strings, ids, and numbers to the text output.
 type WriteStatement struct {
-	Args           []string // the strings, identifiers, or numbers to write
+	Values         *[]*Value
 	TextOutputName string
 }
 

amod/amod.go

@@ -107,7 +107,9 @@ func addACTR(model *actr.Model, list *fieldList, errs *errorListWithContext) {
 		case "log":
 			if field.Value.Number != nil {
 				model.Logging = (*field.Value.Number != 0)
-			} else {
+			} else if field.Value.ID != nil {
+				model.Logging = (strings.ToLower(*field.Value.ID) == "true")
+			} else if field.Value.Str != nil {
 				model.Logging = (strings.ToLower(*field.Value.Str) == "true")
 			}
 		default:
@@ -476,7 +478,7 @@ func addPrintStatement(model *actr.Model, print *printStatement, production *act
 
 	p := actr.PrintStatement{}
 	if print.Args != nil {
-		p.Args = print.Args.Strings()
+		p.Values = convertArgs(print.Args.Values)
 	}
 
 	s := actr.Statement{Print: &p}
@@ -492,9 +494,31 @@ func addWriteStatement(model *actr.Model, write *writeStatement, production *act
 
 	s := actr.Statement{
 		Write: &actr.WriteStatement{
-			Args:           write.Args.Strings(),
+			Values:         convertArgs(write.Args.Values),
 			TextOutputName: write.TextOutputName},
 	}
 
 	return &s, nil
 }
+
+func convertArgs(values []*value) *[]*actr.Value {
+	actrValues := []*actr.Value{}
+
+	for _, v := range values {
+		newValue := actr.Value{}
+
+		if v.Var != nil {
+			newValue.Var = v.Var
+		} else if v.ID != nil {
+			newValue.ID = v.ID
+		} else if v.Str != nil {
+			newValue.Str = v.Str
+		} else if v.Number != nil {
+			newValue.Number = v.Number
+		}
+
+		actrValues = append(actrValues, &newValue)
+	}
+
+	return &actrValues
+}

amod/amod_test.go

@@ -307,10 +307,11 @@ func TestProductionPrintStatement(t *testing.T) {
 	==model==
 	name: Test
 	==config==
+	chunks { foo( thing1 thing2 ) }
 	==productions==
 	start {
-		match { memory ` + "`_status( error )`" + ` }
-		do { print 42 }
+		match { goal ` + "`foo( ?next ?other )`" + ` }
+		do { print 42, ?other, "blat" }
 	}`
 
 	_, err := GenerateModel(src)
@@ -333,6 +334,34 @@ func TestProductionPrintStatement(t *testing.T) {
 	if err != nil {
 		t.Errorf("Unexpected error: %s", err)
 	}
+
+	src = `
+	==model==
+	name: Test
+	==config==
+	==productions==
+	start {
+		match { memory ` + "`_status( error )`" + ` }
+		do { print fooID }
+	}`
+
+	_, err = GenerateModel(src)
+	expected := "cannot use ID 'fooID' in print statement (line 8)"
+	checkExpectedError(err, expected, t)
+
+	src = `
+	==model==
+	name: Test
+	==config==
+	==productions==
+	start {
+		match { memory ` + "`_status( error )`" + ` }
+		do { print ?fooVar }
+	}`
+
+	_, err = GenerateModel(src)
+	expected = "print statement variable '?fooVar' not found in matches for production 'start' (line 8)"
+	checkExpectedError(err, expected, t)
 }
 
 func TestProductionMatchInternal(t *testing.T) {

amod/lex.go

@@ -346,11 +346,7 @@ func lexStart(l *lexer_amod) stateFn {
 		l.emit(lexemePatternDelim)
 
 	case r == '?':
-		if l.inPattern {
-			return lexIdentifier
-		} else {
-			l.emit(lexemeChar)
-		}
+		return lexIdentifier
 
 	case r <= unicode.MaxASCII && unicode.IsPrint(r):
 		l.emit(lexemeChar)
@@ -450,6 +446,8 @@ func lexIdentifier(l *lexer_amod) stateFn {
 		isKeyword := l.lookupKeyword(l.input[l.start:l.pos])
 		if isKeyword {
 			l.emit(lexemeKeyword)
+		} else if l.input[l.start] == '?' {
+			l.emit(lexemePatternVar)
 		} else {
 			l.emit(lexemeIdentifier)
 		}

amod/parse.go

@@ -1,7 +1,6 @@
 package amod
 
 import (
-	"fmt"
 	"io"
 	"os"
 
@@ -42,38 +41,20 @@ type stringList struct {
 }
 
 type value struct {
-	Str    *string  `parser:"  (@String|@Ident)"`
-	Number *float64 `parser:"| @Number"`
+	Var    *string  `parser:"( @PatternVar"`
+	ID     *string  `parser:"| @Ident"`
+	Str    *string  `parser:"| @String"`
+	Number *float64 `parser:"| @Number)"`
 
 	Pos lexer.Position
 }
 
-func (v *value) String() string {
-	if v.Str != nil {
-		return *v.Str
-	} else if v.Number != nil {
-		return fmt.Sprintf("%f", *v.Number)
-	}
-
-	return ""
-}
-
 type argList struct {
-	Args []*value `parser:"( @@ ','? )+"`
+	Values []*value `parser:"( @@ ','? )+"`
 
 	Pos lexer.Position
 }
 
-// Strings converts an arg list into a string slice
-func (a *argList) Strings() []string {
-	str := make([]string, len(a.Args))
-	for i, arg := range a.Args {
-		str[i] = arg.String()
-	}
-
-	return str
-}
-
 type field struct {
 	Key   string `parser:"@Ident ':'"`
 	Value value  `parser:"@@ (',')?"`

amod/validate.go

@@ -197,6 +197,19 @@ func validateClearStatement(clear *clearStatement, model *actr.Model, production
 func validatePrintStatement(print *printStatement, model *actr.Model, production *actr.Production) (err error) {
 	errs := errorListWithContext{}
 
+	if print.Args != nil {
+		for _, v := range print.Args.Values {
+			if v.ID != nil {
+				errs.Addc(&print.Pos, "cannot use ID '%s' in print statement", *v.ID)
+			} else if v.Var != nil {
+				match := production.LookupMatchByVariable(*v.Var)
+				if match == nil {
+					errs.Addc(&print.Pos, "print statement variable '%s' not found in matches for production '%s'", *v.Var, production.Name)
+				}
+			}
+		}
+	}
+
 	return errs.ErrorOrNil()
 }
 
@@ -210,5 +223,18 @@ func validateWriteStatement(write *writeStatement, model *actr.Model, production
 		errs.Addc(&write.Pos, "text output '%s' not found in production '%s'", name, production.Name)
 	}
 
+	if write.Args != nil {
+		for _, v := range write.Args.Values {
+			if v.ID != nil {
+				errs.Addc(&write.Pos, "cannot use ID '%s' in write statement", *v.ID)
+			} else if v.Var != nil {
+				match := production.LookupMatchByVariable(*v.Var)
+				if match == nil {
+					errs.Addc(&write.Pos, "write statement variable '%s' not found in matches for production '%s'", *v.Var, production.Name)
+				}
+			}
+		}
+	}
+
 	return errs.ErrorOrNil()
 }

examples/addition.amod

@@ -58,7 +58,7 @@ terminateAddition {
         goal `add( ?num1 ?num2 ?num2 ?sum )`
     }
     do {
-        print sum
+        print ?sum
         clear goal
     }
 }

examples/addition2.amod

@@ -18,7 +18,7 @@ actr { log: true }
 
 // Declare chunks and their layouts
 chunks {
-    add( slot_1 slot_2 slot_3 slot_4 slot_5 slot_6 slot_7 )
+    add( slot_1 slot_2 slot_3 slot_4 slot_5 answer remainder )
     addFact( first second sum )
 }
 
@@ -42,7 +42,7 @@ startPair {
     }
     // Steps to execute
     do {
-        set slot_6 of goal to 'busy'
+        set answer of goal to 'busy'
         recall `addFact( ?one1 ?one2 ? )`
     }
 }
@@ -53,8 +53,8 @@ addOnes {
         retrieval `addFact( ? ? ?sum )`
     }
     do {
-        set slot_6 of goal to sum
-        set slot_7 of goal to 'busy'
+        set answer of goal to sum
+        set remainder of goal to 'busy'
         recall `addFact( 10 ? ?sum )`
     }
 }
@@ -66,8 +66,8 @@ processCarry {
     }
     do {
         set slot_5 of goal to 'busy'
-        set slot_6 of goal to rem
-        set slot_7 of goal to 1
+        set answer of goal to rem
+        set remainder of goal to 1
         recall `addFact( ?ten1 ?ten2 ? )`
     }
 }
@@ -79,7 +79,7 @@ noCarry {
     }
     do {
         set slot_4 of goal to 'busy'
-        set slot_6 of goal to 0
+        set answer of goal to 0
         recall `addFact( ?ten1 ?ten2 ? )`
     }
 }
@@ -90,7 +90,7 @@ addTensDone {
         retrieval `addFact( ? ? ?sum )`
     }
     do {
-        print sum, oneAns
+        print ?sum, ?oneAns
         set slot_5 of goal to sum
     }
 }
@@ -101,7 +101,7 @@ addTensCarry {
         retrieval `addFact( ? ? ?sum )`
     }
     do {
-        set slot_7 of goal to 0
+        set remainder of goal to 0
         recall `addFact( 1 ?sum ? )`
     }
 }

examples/count.amod

@@ -60,7 +60,7 @@ increment {
         retrieval `count( ?x ?next )`
     }
     do {
-        print x
+        print ?x
         recall `count( ?next ? )`
         set start of goal to next
     }
@@ -71,7 +71,7 @@ stop {
         goal `countFrom( ?x ?x counting )`
     }
     do {
-        print x
+        print ?x
         clear goal
     }
 }