Merge pull request #578 from quantified-uncertainty/reducer-dev

Reducer:  Add Units (reimplemented)

packages/squiggle-lang/__tests__/Reducer/Reducer_Peggy/Reducer_Peggy_Parse_test.res

@@ -251,6 +251,10 @@ describe("Peggy parse", () => {
       "{(::map (::$_constructArray_$ (1 2 3)) {|:x| {(::add :x 1)}})}",
     )
   })
+  describe("unit", () => {
+    testParse("1m", "{(::fromUnit_m 1)}")
+    testParse("1m+2cm", "{(::add (::fromUnit_m 1) (::fromUnit_cm 2))}")
+  })
 })
 
 describe("parsing new line", () => {

packages/squiggle-lang/src/rescript/Reducer/Reducer_ErrorValue.res

@@ -4,18 +4,19 @@ type errorValue =
   | REArrayIndexNotFound(string, int)
   | REAssignmentExpected
   | REDistributionError(DistributionTypes.error)
-  | REOperationError(Operation.operationError)
+  | REExpectedType(string)
   | REExpressionExpected
   | REFunctionExpected(string)
   | REFunctionNotFound(string)
   | REJavaScriptExn(option<string>, option<string>) // Javascript Exception
   | REMacroNotFound(string)
   | RENotAFunction(string)
+  | REOperationError(Operation.operationError)
   | RERecordPropertyNotFound(string, string)
   | RESymbolNotFound(string)
   | RESyntaxError(string)
   | RETodo(string) // To do
-  | REExpectedType(string)
+  | REUnitNotFound(string)
 
 type t = errorValue
 
@@ -52,4 +53,5 @@ let errorToString = err =>
   | RESyntaxError(desc) => `Syntax Error: ${desc}`
   | RETodo(msg) => `TODO: ${msg}`
   | REExpectedType(typeName) => `Expected type: ${typeName}`
+  | REUnitNotFound(unitName) => `Unit not found: ${unitName}`
   }

packages/squiggle-lang/src/rescript/Reducer/Reducer_Peggy/Reducer_Peggy_GeneratedParser.peggy

@@ -248,8 +248,7 @@ basicValue = valueConstructor / basicLiteral
  
 basicLiteral
   = string
-  / float
-  / integer
+  / number
   / boolean
   / dollarIdentifier
 
@@ -263,6 +262,15 @@ string 'string'
   = characters:("'" @([^'])* "'") {return nodeString(characters.join(''))} 
   / characters:('"' @([^"])* '"') {return nodeString(characters.join(''))}
 
+number = number:(float / integer) unit:identifier?
+  { 
+    if (unit === null)
+      { return number }
+    else
+      { return makeFunctionCall('fromUnit_'+unit.value, [number]) 
+      }
+  }
+
 integer 'integer'
   = d+ !"\." ![e]i
   { return nodeInteger(parseInt(text()))}