use syntax T and F for true and false Booleans

Closes #373.

src/Disco/AST/Surface.hs

@@ -543,7 +543,7 @@ instance Pretty Term where
         Nothing -> error $ "pretty @Term: Prim " ++ show p ++ " is not in the primMap!"
     TParens t -> pretty t
     TUnit -> text "■"
-    (TBool b) -> text (map toLower $ show b)
+    (TBool b) -> text (take 1 $ show b)
     TChar c -> text (show c)
     TString cs -> doubleQuotes $ text cs
     TAbs q bnd -> withPA initPA $

src/Disco/Parser.hs

@@ -399,6 +399,8 @@ reservedWords =
   , "false"
   , "True"
   , "False"
+  , "T"
+  , "F"
   , "let"
   , "in"
   , "is"
@@ -695,8 +697,8 @@ parseAtom :: Parser Term
 parseAtom =
   label "expression" $
     parseUnit
-      <|> TBool True <$ (reserved "true" <|> reserved "True")
-      <|> TBool False <$ (reserved "false" <|> reserved "False")
+      <|> TBool True <$ (reserved "true" <|> reserved "True" <|> reserved "T")
+      <|> TBool False <$ (reserved "false" <|> reserved "False" <|> reserved "F")
       <|> TChar <$> lexeme (between (char '\'') (char '\'') L.charLiteral)
       <|> TString <$> lexeme (char '"' >> manyTill L.charLiteral (char '"'))
       <|> TWild <$ try parseWild

src/Disco/Value.hs

@@ -79,7 +79,7 @@ import qualified Prelude as P
 
 import Control.Monad (forM)
 import Data.Bifunctor (first)
-import Data.Char (chr, ord, toLower)
+import Data.Char (chr, ord)
 import Data.IntMap (IntMap)
 import qualified Data.IntMap as IM
 import Data.List (foldl')
@@ -471,7 +471,7 @@ prettyValue (TyUser x args) v = do
   prettyValue (body args) v
 prettyValue _ VUnit = "■"
 prettyValue TyProp _ = prettyPlaceholder TyProp
-prettyValue TyBool (VInj s _) = text $ map toLower (show (s == R))
+prettyValue TyBool (VInj s _) = text $ take 1 (show (s == R))
 prettyValue TyBool v =
   error $ "Non-VInj passed with Bool type to prettyValue: " ++ show v
 prettyValue TyC (vchar -> c) = text (show c)

test/arith-count/expected

@@ -17,10 +17,10 @@
 1
 10
 45
-true
-true
+T
+T
 12600
-true
+T
 2520
 0
 3628800

test/arith-numthry/expected

@@ -1,12 +1,12 @@
 3
 3
-true
-true
-true
-true
-true
-false
-false
-false
-true
-true
+T
+T
+T
+T
+T
+F
+F
+F
+T
+T

test/containers-cmp/expected

@@ -1,4 +1,4 @@
 {{1, 2}, {1, 3}, {2, 3}}
-true
+T
 {⟅1 # 3⟆, ⟅2 # 5⟆}
-true
+T

test/containers-ops/expected

@@ -8,9 +8,9 @@
 {(1, 10), (1, 20), (1, 30), (2, 10), (2, 20), (2, 30)}
 {(1, 10), (1, 20), (1, 30), (2, 10), (2, 20), (2, 30)}
 {1}
-true
-true
-true
+T
+T
+T
 {{}, {1}, {1, 2}, {1, 2, 3}, {1, 3}, {2}, {2, 3}, {3}}
 {{}}
 {{}, {1}}
@@ -29,31 +29,31 @@ bag([2, -3]) union bag([1 / 2]) : Bag(ℚ)
 ⟅⟆
 ⟅2 # 2, 3, 5⟆
 ⟅1⟆
-true
-true
-true
+T
+T
+T
 ⟅⟅⟆⟆
 ⟅⟅⟆, ⟅1⟆⟆
 ⟅⟅⟆, ⟅1⟆, ⟅1, 2⟆, ⟅2⟆⟆
 ⟅⟅⟆, ⟅'a'⟆, ⟅'a', 'b'⟆ # 2, ⟅'a', 'b' # 2⟆, ⟅'b'⟆ # 2, ⟅'b' # 2⟆⟆
 ⟅⟅⟆, ⟅'a'⟆ # 2, ⟅'a', 'b'⟆ # 6, ⟅'a', 'b' # 2⟆ # 6, ⟅'a', 'b' # 3⟆ # 2, ⟅'a' # 2⟆, ⟅'a' # 2, 'b'⟆ # 3, ⟅'a' # 2, 'b' # 2⟆ # 3, ⟅'a' # 2, 'b' # 3⟆, ⟅'b'⟆ # 3, ⟅'b' # 2⟆ # 3, ⟅'b' # 3⟆⟆
 [(2, 3), (2, 4), (2, 4), (1, 3), (1, 4), (1, 4)]
-true
-true
-false
-false
-true
-false
-false
-true
-true
-true
-false
-false
-true
-false
-true
-true
+T
+T
+F
+F
+T
+F
+F
+T
+T
+T
+F
+F
+T
+F
+T
+T
 ⟅'x' # 3, 'y' # 2⟆
 ⟅'x' # 3, 'y'⟆
 ⟅'x', 'y'⟆

test/containers-reduce/expected

@@ -8,8 +8,8 @@ reduce : (a × a → a) × a × List(a) → a
 reduce(~+~, 0, [1 .. 10]) : ℕ
 55
 60
-true
+T
 2351
 6
 7
-true
+T

test/error-tyargs/error-tyargs.disco

@@ -1 +1 @@
-type T(a,b) = Unit + a*b
+type X(a,b) = Unit + a*b

test/error-tyargs/expected

@@ -1,10 +1,10 @@
 Loading error-tyargs.disco...
 Loaded.
-Error: not enough arguments for the type 'T'.
+Error: not enough arguments for the type 'X'.
 https://disco-lang.readthedocs.io/en/latest/reference/num-args-type.html
-Error: not enough arguments for the type 'T'.
+Error: not enough arguments for the type 'X'.
 https://disco-lang.readthedocs.io/en/latest/reference/num-args-type.html
-Error: too many arguments for the type 'T'.
+Error: too many arguments for the type 'X'.
 https://disco-lang.readthedocs.io/en/latest/reference/num-args-type.html
 Error: not enough arguments for the type 'List'.
 https://disco-lang.readthedocs.io/en/latest/reference/num-args-type.html

test/error-tyargs/input

@@ -1,7 +1,7 @@
 :load test/error-tyargs/error-tyargs.disco
-x : T
-y : T(Int)
-z : T(Int,Char)
-w : T(Int,Char,Bool)
+x : X
+y : X(Int)
+z : X(Int,Char)
+w : X(Int,Char,Bool)
 q : List
 p : List(Int,Char)

test/error-unboundtyvar/expected

@@ -1,4 +1,4 @@
 Loading unboundtyvar.disco...
-While checking unboundtyvar.T:
+While checking unboundtyvar.Ty:
   Error: Unknown type variable 'b'.
   https://disco-lang.readthedocs.io/en/latest/reference/unbound-tyvar.html

test/error-unboundtyvar/unboundtyvar.disco

@@ -1 +1 @@
-type T(a) = a + b
+type Ty(a) = a + b

test/graphs-equality/expected

@@ -1,4 +1,4 @@
-true
-true
-true
-true
+T
+T
+T
+T

test/list-poly/expected

@@ -12,7 +12,7 @@
 [10, 9, 8, 7, 6]
 [1, 3, 6, 10, 15, 21]
 [1, 4, 9, 16, 25, 36]
-true
+T
 []
 [1, 3, 4, 4, 3, 1, -2, -6, -11, -17]
 [1, 3/2, 2, 5/2, 3]

test/logic-bools/expected

@@ -1,32 +1,34 @@
-true
-false
-true
-false
-true
-false
-false
-false
-false
-false
-true
-true
-true
-false
-true
-true
-false
-true
-true
-false
-true
-true
-true
-false
-true
-true
-true
-false
-false
-true
-false
-false
+T
+F
+T
+F
+T
+F
+T
+F
+F
+F
+F
+F
+T
+T
+T
+F
+T
+T
+F
+T
+T
+F
+T
+T
+T
+F
+T
+T
+T
+F
+F
+T
+F
+F

test/logic-bools/input

@@ -2,6 +2,8 @@ true
 false
 True
 False
+T
+F
 true and true
 true and false
 false and true

test/logic-cmp/expected

@@ -1,46 +1,46 @@
-true
-false
-false
-true
-true
-true
-false
-false
-true
-false
-false
-true
-true
-false
-false
-false
-true
-true
-false
-true
-false
-true
-true
-false
-true
-false
-true
-false
-false
-true
-true
-true
-false
-true
-false
-true
-true
-false
-true
-true
-false
-false
-true
+T
+F
+F
+T
+T
+T
+F
+F
+T
+F
+F
+T
+T
+F
+F
+F
+T
+T
+F
+T
+F
+T
+T
+F
+T
+F
+T
+F
+F
+T
+T
+T
+F
+T
+F
+T
+T
+F
+T
+T
+F
+F
+T
 3
 5
 1

test/map-compare/expected

@@ -1,4 +1,4 @@
-true
-true
-true
-true
+T
+T
+T
+T