syntax.txt

Syntax rules for QPL given in EBNF

main:= statement_list

statement := ifthen 
           | measure 
           | while_loop
	   | proc_decl
           | proc_call
	   | allocation 
	   | skip 
           | gate_application
           | block

proc_call  := "call" name "(" var_list ")"
proc_decl  := "proc" name ":" context "->" context block "in" statement
ifthen     := "if" boolean_expr "then" statement "else" statement
measure    := "measure" var "then" statement "else" statement
while_loop := "while" boolean_expr "do" statement
skip       := "skip"
block      := "{" stmt_list "}"

context := var ":" type { "," var ":" type }

arith_expr := number 
            | var
            | arith_expr * arith_expr 
            | arith_expr + arith_expr 
            | arith_expr - arith_expr
            | arith_expr / arith_expr
            | (arith_expr)
boolean_expr := arith_expr { cmp_op arith_expr }
              | !boolean_expr
              | boolean_expr boolean_op boolean_expr
              | "true" 
              | "false"
cmp_op := "<" | ">" | "<=" | ">=" | "!=" 
boolean_op := "&" | "|"

proc_call := "call" name "(" var_list ")"

gate_application := var_list "*=" var

var_list := var { "," var }

stmt_list := statement 
           | statement ";" stmt_list

allocation :=  "new bit" var ":=" inital_value
             | "new qbit" var ":=" inital_value
inital_value := "0" | "1"

type := "bit" | "qbit"
var := 'Alphanumerical name'