| BCPL (Basic CPL) A British systems language developed by Richards in 1969 and descended from (Combined Programming Language). BCPL is low-level, typeless and block-structured, and provides only one-dimensional . Case is not significant, but conventionally reserved words begin with a capital. Flow control constructs include: If-Then, Test-Then-Else, Unless-Do, While-Do, Until-Do, Repeat, Repeatwhile, Repeatuntil, For-to-By-Do, Loop, Break and Switchon-Into-Case-Default-Endcase. BCPL has conditional expressions, pointers, and manifest constants. It has both procedures: 'Let foo(bar) Be command' and functions: 'Let foo(bar) = expression'. 'Valof $(..Resultis..$)' causes a compound command to produce a value. Parameters are . Program segments communicate via the global vector where system and user variables are stored in fixed numerical locations in a single array. The first BCPL was written in . BCPL was used to implement the , which was subsequently reincarnated as . ["BCPL - The Language and its Compiler", Martin Richards & Colin Whitby-Stevens, Cambridge U Press 1979]. See , . Oxford BCPL differed slightly: Test-Ifso-Ifnot, and section brackets in place of $( $). The original for BCPL is available for , , {(ftp://wuarchive.wustl.edu/systems/amiga/programming/languages/BCPL/)}. A BCPL compiler kit with an in was written by Ken Yap . (1995-03-26) |
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