Component Pascal

<h2 id="syntax">Syntax</h2>
<p>The full syntax for CP, as given by the Language Report, is shown below. In the <a href="/facts/Extended_Backus%25E2%2580%2593Naur_form/89KI2QTe">extended Backus–Naur form</a>, only 34 grammatical productions are needed, one more than for <a href="/facts/Oberon-2/ahBack6j">Oberon-2</a>, although it is a more advanced language.
</p>
Module = MODULE ident ";" 
           [ImportList] DeclSeq 
           [BEGIN StatementSeq] 
           [CLOSE StatementSeq] 
         END ident ".".

ImportList = IMPORT [ident ":="] ident {"," [ident ":="] ident} ";".

DeclSeq = { CONST {ConstDecl ";" } 
          | TYPE {TypeDecl ";"} 
          | VAR {VarDecl ";"}} 
          { ProcDecl ";" | ForwardDecl ";"}.

ConstDecl = IdentDef "=" ConstExpr.

TypeDecl = IdentDef "=" Type.

VarDecl = IdentList ":" Type.

ProcDecl = PROCEDURE [Receiver] IdentDef [FormalPars] MethAttributes 
           [";" DeclSeq [BEGIN StatementSeq] 
           END ident].

MethAttributes = ["," NEW] ["," (ABSTRACT | EMPTY | EXTENSIBLE)].

ForwardDecl = PROCEDURE "^" [Receiver] IdentDef [FormalPars] MethAttributes.

FormalPars = "(" [FPSection {";" FPSection}] ")" [":" Type].

FPSection = [VAR | IN | OUT] ident {"," ident} ":" Type.

Receiver = "(" [VAR | IN] ident ":" ident ")".

Type = Qualident
    | ARRAY [ConstExpr {"," ConstExpr}] OF Type
    | [ABSTRACT | EXTENSIBLE | LIMITED] RECORD ["("Qualident")"] FieldList {";" FieldList} END
    | POINTER TO Type
    | PROCEDURE [FormalPars].

FieldList = [IdentList ":" Type].

StatementSeq = Statement {";" Statement}.

Statement = [ Designator ":=" Expr
    | Designator ["(" [ExprList] ")"]
    | IF Expr THEN StatementSeq
        {ELSIF Expr THEN StatementSeq}
        [ELSE StatementSeq] 
      END
    | CASE Expr OF 
        Case {"|" Case}
        [ELSE StatementSeq] 
      END
    | WHILE Expr DO StatementSeq END
    | REPEAT StatementSeq UNTIL Expr
    | FOR ident ":=" Expr TO Expr [BY ConstExpr] DO StatementSeq END
    | LOOP StatementSeq END
    | WITH [ Guard DO StatementSeq ] 
       {"|" [ Guard DO StatementSeq ] } 
       [ELSE StatementSeq] 
      END
    | EXIT
    | RETURN [Expr]
    ].

Case = [CaseLabels {"," CaseLabels} ":" StatementSeq].

CaseLabels = ConstExpr [".." ConstExpr].

Guard = Qualident ":" Qualident.

ConstExpr = Expr.

Expr = SimpleExpr [Relation SimpleExpr].

SimpleExpr = ["+" | "-"] Term {AddOp Term}.

Term = Factor {MulOp Factor}.

Set = "{" [Element {"," Element}] "}".

Element = Expr [".." Expr].

Relation = "=" | "#" | "<" | "<=" | ">" | ">=" | IN | IS.

AddOp = "+" | "-" | OR.

MulOp = "*" | "/" | DIV | MOD | "&".

Designator = Qualident {"." ident 
             | "[" ExprList "]" 
             | "^" 
             | "(" Qualident ")" 
             | "(" [ExprList] ")"} [ "$" ].

ExprList = Expr {"," Expr}.

IdentList = IdentDef {"," IdentDef}.

Qualident = [ident "."] ident.

IdentDef = ident ["*" | "-"].

<h2 id="further-reading">Further reading</h2>
<ul><li><a href="https://doi.org/10.3929/ethz-a-000564136">From Modula to Oberon</a> Wirth (1990)</li>
<li><a href="http://www.inf.ethz.ch/personal/wirth/Oberon/Oberon.Report.pdf">The Programming Language Oberon</a> Wirth (1990)</li>
<li><a href="https://doi.org/10.3929/ethz-a-000589808">Differences between Oberon and Oberon-2</a> Mössenböck and Wirth (1993)</li>
<li><a href="http://www.ssw.uni-linz.ac.at/Research/Papers/Oberon2.pdf">The Programming Language Oberon-2</a> H. Mössenböck, N. Wirth, Institut für Computersysteme, ETH Zürich (<a href="/facts/ETHZ/IxHAFGUU">ETHZ</a>), January 1992.</li>
<li><a href="https://web.archive.org/web/20110515111149/http://www.oberon.ch/pdf/CP-New.pdf">What's New in Component Pascal</a> (changes from Oberon-2 to CP), Pfister (2001)</li>
<li><a href="http://www.drdobbs.com/components-and-objects-together/184415685">Components and Objects Together</a>, Clemens Szyperski, Dr.Dobbs, May, 1999</li></ul>
<h2 id="external-links">External links</h2>
<ul><li><a href="http://blackboxframework.org">Official website</a></li>
<li><a href="https://web.archive.org/web/20191218082105/http://www.oberon.ch/blackbox.html">Last available version of former official website</a> see also <a href="http://blackboxframework.org/index.php?cID=goto-download-page,en-us">historical notes on the download page</a></li>
<li><a href="https://github.com/k-john-gough/gpcp">Gardens Point Component Pascal</a> for .NET & JVM</li>
<li><a href="https://github.com/Oleg-N-Cher/CPFront">Component Pascal to C</a> <a href="/facts/Transpiler/MnSVwoe9">transpiler</a> based on Josef Templ's <a href="https://github.com/jtempl/ofront">OFront</a></li></ul>

<h2 id="references">References</h2>

<ol>
<li id="fn:1"><p>Jensen, Kathleen; Wirth, Niklaus (1974–1991). Pascal: User Manual And Report. Springer Verlag. ISBN 978-0-387-97649-5. <a href="978-0-387-97649-5" target="_blank">978-0-387-97649-5</a> <a href="#fnref:1" class="footnote-back-ref">↩</a></p></li>
<li id="fn:2"><p>Wirth, Niklaus (1982–1985). Programming in Modula-2. Springer Verlag. ISBN 978-3-540-15078-7. <a href="978-3-540-15078-7" target="_blank">978-3-540-15078-7</a> <a href="#fnref:2" class="footnote-back-ref">↩</a></p></li>
<li id="fn:3"><p>Reiser, Martin; Wirth, Niklaus (1 June 1992). Programming in Oberon: Steps Beyond Pascal and Modula. Addison-Wesley. ISBN 978-0201565430. PDF (334 KB) Archived 3 June 2012 at the Wayback Machine <a href="978-0201565430" target="_blank">978-0201565430</a> <a href="#fnref:3" class="footnote-back-ref">↩</a></p></li>
<li id="fn:4"><p>Wirth, Niklaus; Gutknecht, Jürg (1 November 1992). Project Oberon: The Design of an Operating System and Compiler. Addison-Wesley. ISBN 978-0201544282. PDF (4'398 KB) Archived 10 July 2012 at the Wayback Machine <a href="978-0201544282" target="_blank">978-0201544282</a> <a href="#fnref:4" class="footnote-back-ref">↩</a></p></li>
<li id="fn:5"><p>Mössenböck, Hans-Peter; Wirth, Niklaus (1991). "The Programming Language Oberon-2" (PDF). Structured Programming. 12: 179–195. <a href="/wiki/Niklaus_Wirth" target="_blank">/wiki/Niklaus_Wirth</a> <a href="#fnref:5" class="footnote-back-ref">↩</a></p></li>
<li id="fn:6"><p>Mössenböck, H.; Koskimies, K. (1996). "Active Text for Structuring and Understanding Source Code". Software: Practice and Experience. 26 (7): 833–850. doi:10.1002/(SICI)1097-024X(199607)26:7<833::AID-SPE34>3.0.CO;2-Q. <a href="http://onlinelibrary.wiley.com/doi/10.1002/(SICI)1097-024X(199607)26:7%3C833::AID-SPE34%3E3.0.CO;2-Q/pdf" target="_blank">http://onlinelibrary.wiley.com/doi/10.1002/(SICI)1097-024X(199607)26:7%3C833::AID-SPE34%3E3.0.CO;2-Q/pdf</a> <a href="#fnref:6" class="footnote-back-ref">↩</a></p></li>
</ol>

Component Pascal open-in-new

Component Pascal