The body of a procedure consists of executable commands. The last command in the body is a Return and a Return cannot be coded within the body.

A function or a procedure that is declared to be pure is restricted so that they do not have side effects. They can only call other pure procedures and cannot contain input nor output commands. However Trace commands are allowed as they are only intended to be active while debugging. Pure procedures can not raise Error exceptions, but Fault exceptions can be raised by any procedure. Preconditions and Assertion commands in pure procedures can only raise Fault exceptions.

Command Summary Syntax

Assignment

Primitive [(Subcript)]  [Op]=  Expression
User.Tye  [(Subcript)]  =  User

Pointer  =  @Variable
Pointer  =  @Variable( Subcript )
Pointer  =  @Function( [Argument, ...] )
Pointer  =  @parcel( Expression )

Destination  [Op]=  if Condtion  [, Expression  [, Expression]]

Procedure Invokation

Procedure  [[Parameter =]  {Variable | Array | Expression}, ...]

CHURN  from  Container   with  It
CHURN  from  Sequence( Argument, ...)   with  It
CHURN  [@]Result  from  It
CHURN  [@]Result  from  Container   with  It
CHURN  [@]Result  from  Sequence( Argument, ...)   with  It
CHURN  end [It]

YIELD

CLEAN  Subject, ...
DRAIN  Subject, ...  

Control

preconditon
   Condition
   Condition  error  [Context [| Form]] 
   Condition  fault  [Context [| Form]] 
   Condition  catch  Handler
.

assert  Condition
assert  Condition  error  [Context [| Form]]
assert  Condition  fault  [Context [| Form]]
assert  Condition  catch  Handler

DO always
DO while  Condition
DO until  Condition
DO Expression  times
DO Variable [= Numeric]  to  Numeric  [by Numeric]
DO Variable  from  Sequence( Argument.List )

UNDO  IF  Condition
UNDO  '-'*
-

IF Condition
ELSE IF Condition
ELSE
.

IF Expression  is  Value.List
ELSE IS Value.List
ELSE
.

postcondition
return  [raise]

Input and Output

OPEN   {`in | `out | `append | `direct}  [`big | `little]  File '<>'  String.Expression

CLOSE   `file   File

INPUT  File         '<>'  {Variable | Quote}, ...
INPUT  File(Index)  '<>'  {Variable | Quote}, ...
INPUT  `seek  File(Index)  '<>'  Type

PRINT  [`#]  [`err]     [Expression ['|' Form], ...]  [flush]
PRINT  [`#]  File  '<>'  Expression ['|' Form], ...   [flush]
PRINT  [`#]  File(Index)  '<>'  Expression ['|' Form], ... [flush]

trace      [`log | `err | `if | `on | `off]  '/'  
trace       {Quote | {[@] Name [Subscript]  ['|' Format]}} , ...
trace`err  [{Quote | {[@] Name [Subscript]  ['|' Format]}} , ...]
trace`log  [ Path ]

trace`if    Condition  {Quote | {[@] Name [Subscript] ['|' Form]}} , ...
trace`on   [Condition]
trace`off  [Condition]