module IBAF-Start
            
imports 
  
  Funcons

// Language "IBAFlang"
    
lexical syntax // Language
  
  // #1 Arithmetic expressions
                
  
  LEX-DASH = "-"
  LEX-decimal = ( [0-9] )+
  LEX-id = ( [A-Z] | [a-z] )+
  
syntax // Language
  
  // #1 Arithmetic expressions
                
  
  
context-free syntax // Language
  L-start.L-start--L-aexp =
    L-aexp
  
  
  // #1 Arithmetic expressions
                
  
  L-aexp.L-aexp--L-num =
    L-num
  L-aexp.L-aexp--L-id =
    L-id
  L-aexp.L-aexp--L-aexp-PLUS-L-aexp =
    L-aexp "+" L-aexp
  L-aexp.L-aexp--L-aexp-SLASH-L-aexp =
    L-aexp "/" L-aexp
  L-aexp.L-aexp--LPAREN-L-aexp-RPAREN =
    "(" L-aexp ")"
  
  L-decimal.LEX-decimal = 
    LEX-decimal
  L-id.LEX-id = 
    LEX-id
  
context-free syntax // Semantics
  FCT.T-start =
    "start" "[:" L-start ":]"
  
  // #1 Arithmetic expressions
                
  
  FCT.T-eval-arith =
    "eval-arith" "[:" L-aexp ":]"
  FCT-Quoted.L-decimal = L-decimal
  FCT.T-int-val =
    "int-val" "[:" L-num ":]"
  FCT-Quoted.L-id = L-id
  FCT.T-id =
    "id" "[:" L-id ":]"
  
context-free syntax // Desugaring
  
  // #1 Arithmetic expressions
                
  
  
variables // Meta-variables
  L-start = "(:START" [1-9]? ":)" {prefer}
  L-start? = "(:START" [1-9]? "?:)" {prefer}
  L-start* = "(:START" [1-9]? "*:)" {prefer}
  L-start+ = "(:START" [1-9]? "+:)" {prefer}
  
  // #1 Arithmetic expressions
                
  
  L-aexp = "(:AExp" [1-9]? ":)" {prefer}
  L-aexp? = "(:AExp" [1-9]? "?:)" {prefer}
  L-aexp* = "(:AExp" [1-9]? "*:)" {prefer}
  L-aexp+ = "(:AExp" [1-9]? "+:)" {prefer}
  L-num = "(:N" [1-9]? ":)" {prefer}
  L-num? = "(:N" [1-9]? "?:)" {prefer}
  L-num* = "(:N" [1-9]? "*:)" {prefer}
  L-num+ = "(:N" [1-9]? "+:)" {prefer}
  L-decimal = "(:D" [1-9]? ":)" {prefer}
  L-decimal? = "(:D" [1-9]? "?:)" {prefer}
  L-decimal* = "(:D" [1-9]? "*:)" {prefer}
  L-decimal+ = "(:D" [1-9]? "+:)" {prefer}
  L-id = "(:I" [1-9]? ":)" {prefer}
  L-id? = "(:I" [1-9]? "?:)" {prefer}
  L-id* = "(:I" [1-9]? "*:)" {prefer}
  L-id+ = "(:I" [1-9]? "+:)" {prefer}
  
// SDF comments
  
  // #1 Arithmetic expressions
                
  
  
sorts // ASTs
  T-start