diff -r 84eb4d58dd04 -r 14f0caf53e2f UnitConverter.st
--- a/UnitConverter.st	Wed Aug 06 00:57:59 1997 +0200
+++ b/UnitConverter.st	Thu Aug 07 12:55:32 1997 +0200
@@ -48,6 +48,7 @@
         Transcript showCR:
             (UnitConverter convert:1 from:#liter to:#floz)
                                                                 [exEnd]
+
     or, how many square-meters an acre is:
                                                                 [exBegin]
         Transcript showCR:
@@ -64,11 +65,12 @@
                                                                 [exEnd]
 
 
-    how fast do I drive ?
+    how fast do I drive ? :-)
                                                                 [exBegin]
         Transcript showCR:(
                 UnitConverter convert:200 from:#'km/hr' to:#'mile/hr')
                                                                 [exEnd]
+    how fast does Chris drive ? :-)
                                                                 [exBegin]
         Transcript showCR:(
                 UnitConverter convert:65 from:#'mile/hr' to:#'km/hr')
@@ -86,6 +88,29 @@
                                                                 [exEnd]
 
 
+    distances:
+        
+                                                                [exBegin]
+        Transcript showCR:(
+            UnitConverter convert:1 from:#'lightsecond' to:#'kilometer') 
+                                                                [exEnd]
+    thats the same:
+                                                                [exBegin]
+        Transcript showCR:(
+            UnitConverter convert:1 from:#'lightspeed*s' to:#'kilometer') 
+                                                                [exEnd]
+    a days travel ...
+                                                                [exBegin]
+        Transcript showCR:(
+            UnitConverter convert:1 from:#'lightspeed*dy' to:#'kilometer') 
+                                                                [exEnd]
+    a year travel ...
+                                                                [exBegin]
+        Transcript showCR:(
+            UnitConverter convert:1 from:#'lightyear' to:#'kilometer') 
+                                                                [exEnd]
+
+
     real estate buyers might want to know, how many acres
     a german ar is:
                                                                 [exBegin]
@@ -98,7 +123,12 @@
             (UnitConverter convert:100 from:#'meter^2' to:#'foot^2')   
                                                                 [exEnd]
 
-
+    how many tea spoons are there in a cubic meter ?
+    (roughly, since a teaspoon is not a standard unit)
+                                                                [exBegin]
+        Transcript showCR:
+            (UnitConverter convert:1 from:#'meter^3' to:#teaspoon)
+                                                                [exEnd]
     how wide is a US page in inches:
                                                                 [exBegin]
         Transcript showCR:
@@ -163,6 +193,11 @@
     Scaling at:#atto  put:(1/1000000000000000000).
 
 
+    "/ ---------- velocity -------------
+
+    Constants at:#lightSpeed   put:#(2.997925E8   #'m/s').
+
+
     "/ -------------- length -------------
 
     Aliases at:#km       put:#kilometer.
@@ -191,6 +226,7 @@
     "/ nautic
     self addConversion:1852        from:#'nautical-mile' to:#meter.
 
+    self addConversion:((Constants at:#lightspeed) at:1) from:#'lightspeed*s' to:#'meter'.
 
     "/ ---------- time -------------
 
@@ -200,11 +236,6 @@
     self addConversion:365.24219879 from:#yr  to:#dy.
 
 
-    "/ ---------- velocity -------------
-
-    Constants at:#lightSpeed   put:#(2.997925E8   #'m/s').
-
-
     "/ ---------- printing -------------
 
     "/ inch to (roughly) a typesetter point
@@ -381,8 +412,45 @@
      UnitConverter initialize
     "
 
-    "Modified: 29.3.1997 / 19:11:52 / cg"
     "Created: 22.7.1997 / 13:56:40 / cg"
+    "Modified: 6.8.1997 / 17:16:00 / cg"
+! !
+
+!UnitConverter class methodsFor:'accessing'!
+
+scalings
+    "return the set of known scaling prefixes"
+
+    ^ Scaling keys
+
+    "
+     UnitConverter scalings
+    "
+
+    "Created: 6.8.1997 / 16:53:19 / cg"
+    "Modified: 6.8.1997 / 16:58:11 / cg"
+!
+
+units
+    "return the set of known units"
+
+    |setOfUnits|
+
+    setOfUnits := IdentitySet new.
+    Conversions keysAndValuesDo:[:srcUnit :conversionInfo |
+        setOfUnits add:srcUnit.
+        conversionInfo keysDo:[:targetUnit |
+            setOfUnits add:targetUnit
+        ]
+    ].
+    ^ setOfUnits
+
+    "
+     UnitConverter units
+    "
+
+    "Created: 6.8.1997 / 16:57:08 / cg"
+    "Modified: 6.8.1997 / 16:57:47 / cg"
 ! !
 
 !UnitConverter class methodsFor:'conversions'!
@@ -397,6 +465,8 @@
      sF1 sF2 dF1 dF2
      s d|
 
+"/ Transcript showCR:('try ' , sourceUnit , '->' , destUnit).
+
     Conversions isNil ifTrue:[
         self initializeConversions
     ].
@@ -467,6 +537,11 @@
         ^ self convert:(howMany*val) from:unit to:destUnit
     ].
 
+    "/ compounds (^ , / or *) are very naively parsed
+    "/ need a full expression parser (tree) for full power.
+    "/ I leave that as an excercise to you ...
+
+
     "/ working with squares or cubics ?
 
     ((sourceUnit endsWith:'^2') and:[destUnit endsWith:'^2']) ifTrue:[
@@ -564,6 +639,36 @@
         ].
     ].
 
+    "/ if working with a product, try each component
+
+    (sourceUnit includes:$*) ifTrue:[
+        i := sourceUnit indexOf:$*.
+        sF1 := sourceUnit copyTo:(i - 1).
+        sF2 := sourceUnit copyFrom:(i + 1).
+
+        "/ see what we have ...
+
+        self units do:[:aUnit |
+            |pref iUnit factor2 rslt|
+
+            pref := sF1 , '*'.
+            (aUnit startsWith:pref) ifTrue:[
+                "/ ok; want a/b -> x
+                "/ found a/c -> any
+                "/ what about c->b ?
+
+                iUnit := aUnit copyFrom:pref size + 1.
+                factor2 := self convert:1 from:sF2 to:iUnit.
+                factor2 notNil ifTrue:[
+                    "/ good ...
+                    rslt := self convert:(factor2 * howMany)
+                                    from:aUnit to:destUnit.
+                    rslt notNil ifTrue:[^ rslt].
+                ]
+            ]
+        ].
+    ].
+
     ^ self noConversionFrom:sourceUnit to:destUnit.
 
     "direct - how many meters are there in two inches:
@@ -594,7 +699,7 @@
     "
 
     "Created: 31.5.1996 / 16:23:38 / cg"
-    "Modified: 22.7.1997 / 13:57:20 / cg"
+    "Modified: 6.8.1997 / 18:10:22 / cg"
 !
 
 inchToMillimeter:inches
@@ -709,5 +814,5 @@
 !UnitConverter class methodsFor:'documentation'!
 
 version
-    ^ '$Header: /cvs/stx/stx/libbasic2/UnitConverter.st,v 1.10 1997-07-22 11:58:06 cg Exp $'
+    ^ '$Header: /cvs/stx/stx/libbasic2/UnitConverter.st,v 1.11 1997-08-07 10:55:32 cg Exp $'
 ! !