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Generating Software from Specifications WS 2013/14 - File Statements.fw

@=~
~p maximum_input_line_length = infinity

This file contains the specification of a processor
for a little programming language with variable declarations,
nested blocks, assignments, and some control-flow statements.

The following file contains correct input for the processor:
~O~<Statements.ok~>~{~-
{
  int i;
  i = 5;
  while (i) i = 0;
  { int x; x = 21; }
  int j;
  if (j) j = 1;
  { int k; k = i;
    { k = 42; }
  }
  { i = 42; }
}
~}

The following file contains erroneous input for the processor:
~O~<Statements.err~>~{
~}

The following file specifies the concrete syntax:
~O~<Statements.con~>~{
Program:	Block.
Block:		'{' Constructs '}'.

Constructs:	Constructs Construct / Construct.
Construct:	Declaration.
Construct:	Statement.

Declaration:	'int' VarNameDef ';'.
VarNameDef:	Identifier.

Statement:	VarNameUse '=' Expression ';' /
		'while' '(' Expression ')' Statement /
		'if' '(' Expression ')' Statement /
		Block.

Expression:	VarNameUse / Number .
VarNameUse:	Identifier.
~}

The following file specifies the non-literal tokens:
~O~<Statements.gla~>~{
Identifier: C_IDENTIFIER
Number:     C_INTEGER
            C_COMMENT
~}

The following file specifies the abstract sxntax.
It is recommended not to add computations to these
rule instances; rather copy rules to other lido fragments
and add computations there.
~O~<Abstract.lido~>~{
RULE: Program ::= Block COMPUTE END;
RULE: Block ::= '{' Constructs '}' COMPUTE END;

RULE: Constructs ::= Constructs Construct COMPUTE END;
RULE: Constructs ::= Construct COMPUTE END;
RULE: Construct ::= Declaration COMPUTE END;
RULE: Construct ::= Statement COMPUTE END;

RULE: Declaration ::= 'int' VarNameDef ';' COMPUTE END;
RULE: VarNameDef ::= Identifier COMPUTE END;

RULE: Statement ::= VarNameUse '=' Expression ';' COMPUTE END;
RULE: Statement ::= 'while' '(' Expression ')' Statement COMPUTE END;
RULE: Statement ::= 'if' '(' Expression ')' Statement COMPUTE END;
RULE: Statement ::= Block COMPUTE END;

RULE: Expression ::= VarNameUse COMPUTE END;
RULE: Expression ::= Number COMPUTE END;
RULE: VarNameUse ::= Identifier COMPUTE END;
~}

The solutions of subtasks are to be inserted into the following
macros:

Subtask-1:
Unique numbers for statements in any order:
~O~<Subtask-1.lido~>~{

~}

Subtask-2:
Deactivate the previous solution.
Unique numbers for statements in left-to-right order computed by a CHAIN:
~O~<Subtask-2.lido~>~{

~}

Subtask-3:
Deactivate the previous solution.
Count occurrences of VarNameUse:
~O~<Subtask-3.lido~>~{

~}

Subtask-4:
Compute nesting depth of blocks and output in the context of
a defining occurrence of a variable the depth of the surrounding block:
~O~<Subtask-4.lido~>~{

~}

Subtask-5:
Produce first output at all definig occurrences of variables,
then at all applied occurrences:
~O~<Subtask-5.lido~>~{

~}

The following files makes a module available that defines
the datatype CharPtr for strings and functions for string
concatenation:
~O~<Post.specs~>~{
$/Tech/Strings.specs
~}

The following three files implements some C functions which
may be used in the generated processor:
~O~<Statements.HEAD.phi~>==~{
#include "Statements.h"
~}
~O~<Statements.h~>==~{
~}
~O~<Statements.c~>==~{
#include <stdio.h>
#include <string.h>
#include "Statements.h"
~}

Generiert mit Camelot | Probleme mit Camelot? | Geändert am: 13.11.2013