Train Tables

Introduction

The following tables list many possible expressions involving one or two arguments and one or more functions, along with their corresponding Train. These entries may be used to construct the Train which corresponds to more complicated expressions. For example, the expression

L e (L f R) g L h R

may be expressed as a Train as follows:

	L e (L f R) g L h R
←→	L e L (f g h) R		using the definition of Dyadic Fork
←→	L (⊣ e (f g h)) R		using the Train for L g L h R

Tables

gR:

         g R			g
       R g R			(g ⊢)

Other gR forms using g twice may be obtained from ghR below.

LgR:

           L			(⊣ ⊣)
           R			(⊢ ⊢)
         g R			(⊢ g)
         g L			(⊢ g)⍨
       R g R			(⊢ g ⊢)		(⊢ g⍨)
       R g L			g⍨              (g ⊢)⍨          (⊢ g ⊣)
       L g L			(⊣ g ⊣)
       L g R			g               (g ⊢)

Other LgR forms using g twice may be obtained from LghR below.

ghR:

       g h R			((⊢ g) h)
     R g h R			(g h)           Monadic Hook
   g R   h R			((⊢ g) (h ⊢))
  (g R)  h R			(g h ⊢)		(h⍨ g)
 R g R   h R			(g (h ⊢))
(R g R)  h R			((g ⊢) h ⊢)

LghR:

   g     h R			((⊢ g) h)
   g L   h R			(⊢ (⊢ g) h)
  (g L)  h R			(h⍨ g)⍨
 L g     h L			(⊣ g (⊢ h)⍨)
 L g     h R			(g h)          Dyadic Hook
 R g     h R			(⊢ g (⊢ h))
 R g     h L			(g h)⍨
 L g L   h L			(⊣ g ⊣ h ⊣)
 L g L   h R			(⊣ g h)
 L g R   h L			(⊢ g h)⍨
 L g R   h R			(g (h ⊢))
 R g L   h L			(g (h ⊢))⍨
 R g L   h R			(⊢ g h)
 R g R   h L			(⊣ g h)⍨
 R g R   h R			(⊢ g ⊢ h ⊢)
(L g L)  h L			((⊢ g⍨) h ⊢)⍨
(L g L)  h R			(h⍨ (g ⊢))⍨
(L g R)  h L			(g h ⊣)
(L g R)  h R			(g h ⊢)
(R g L)  h L			(g h ⊢)⍨
(R g L)  h R			(g h ⊣)⍨
(R g R)  h L			(h⍨ (g ⊢))
(R g R)  h R			((⊢ g⍨) h ⊢)

fghR:

  (f R) g   h R                (f g h)      Monadic Fork

LfghR:

(L f R) g L h R                (f g h)      Dyadic Fork

Further Study

If you want to better understand this feature, the following workspace might be helpful. It contains functions to aid in understanding Trains such that you can enter a Train (say) L (f g h ⊢) R and it'll output the equivalent expression L f (g R) h R.