libm3/src/fmtlex/Scan.i3

 Copyright (C) 1994, Digital Equipment Corporation.         
 All rights reserved.                                       
 See the file COPYRIGHT for a full description.             
 Last modified on Fri Feb 25 14:22:24 PST 1994 by kalsow    
      modified on Tue Nov 30 23:33:48 PST 1993 by heydon    
      modified on Wed Oct  6 09:09:31 PDT 1993 by mcjones   
      modified on Mon Feb 15 14:17:17 PST 1993 by ramshaw   
      modified on Sun Jun  3 14:25:23 PST 1991 by luca      


 The Scan interface provides procedures for reading strings,
   booleans, integers, and floating-point numbers from a text string.
   Similar functionality on readers is availble from the Lex
   interface. 


INTERFACE Scan;

IMPORT Word, Lex, FloatMode;

 Each of these procedures parses a string of characters and converts
   it to a binary value.  Leading and trailing blanks (ie. characters
   in Lex.Blanks) are ignored.  Lex.Error is raised if the first
   non-blank substring is not generated by the corresponding Lex
   grammar or if there are zero or more than one non-blank substrings.
   FloatMode.Trap is raised as per Lex. 


PROCEDURE Bool(txt: TEXT): BOOLEAN
  RAISES {Lex.Error};

PROCEDURE Int(txt: TEXT; defaultBase: [2..16] := 10): INTEGER
  RAISES {Lex.Error, FloatMode.Trap};
PROCEDURE Unsigned(txt: TEXT; defaultBase: [2..16] := 16): Word.T
  RAISES {Lex.Error, FloatMode.Trap};

PROCEDURE Real(txt: TEXT): REAL
  RAISES {Lex.Error, FloatMode.Trap};
PROCEDURE LongReal(txt: TEXT): LONGREAL
  RAISES {Lex.Error, FloatMode.Trap};
PROCEDURE Extended(txt: TEXT): EXTENDED
  RAISES {Lex.Error, FloatMode.Trap};

END Scan.