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COBOL (Wasm)

COBOL is a compiled, imperative programming language designed for business data processing.

COBOL in LiveCodes is compiled to WebAssembly by the real GnuCOBOL compiler and run in the browser, with no server. The toolchain translates COBOL to C, compiles that with Clang, links libcob, and runs the resulting WebAssembly module.

Usage​

Demo:

show code
import { createPlayground } from 'livecodes';

const options = {
  "config": {
    "activeEditor": "script",
    "script": {
      "language": "cobol-wasm",
      "content": "IDENTIFICATION DIVISION.\nPROGRAM-ID. HELLO-WORLD.\nPROCEDURE DIVISION.\n    DISPLAY \"Hello, World!\".\n    STOP RUN."
    },
    "mode": "simple",
    "editor": "auto",
    "tools": {
      "status": "full"
    }
  }
};
createPlayground('#container', options);

Communication with JavaScript​

The program runs in the context of the result page. A few helpers are available in the browser global livecodes.cobol object:

  • livecodes.cobol.input: the standard input passed to the program.
  • livecodes.cobol.loaded: a promise that resolves when the compiler has downloaded and the program has run, and rejects if the toolchain fails to load. Other helpers should be used after it resolves.
  • livecodes.cobol.output: the program's output (stdout and stderr combined).
  • livecodes.cobol.error: the compiler diagnostics, if the code failed to compile.
  • livecodes.cobol.exitCode: the exit code of the program.
  • livecodes.cobol.run: compiles and runs the code again with new input, returning a promise that resolves with output, error and exitCode.

Example:

show code
import { createPlayground } from 'livecodes';

const options = {
  "template": "cobol-wasm",
  "params": {
    "activeEditor": "markup"
  }
};
createPlayground('#container', options);

IDENTIFICATION DIVISION.
PROGRAM-ID. HELLO-WORLD.
PROCEDURE DIVISION.
    DISPLAY "Hello, World!".
    STOP RUN.

ACCEPT reads from the stdin pane, in the same way as the other console languages:

IDENTIFICATION DIVISION.
PROGRAM-ID. GREET.
DATA DIVISION.
WORKING-STORAGE SECTION.
01 WS-NAME PIC X(20).
PROCEDURE DIVISION.
    ACCEPT WS-NAME
    DISPLAY "Hello, " WS-NAME
    STOP RUN.

Language Info​

Name​

cobol-wasm

Aliases / Extensions​

cobol, cob, cbl, cpy, gnucobol, wasm.cobol

Editor​

script

Compiler​

GnuCOBOL 3.2 compiled to WebAssembly, with Clang and LLD for the generated C.

Custom Settings​

The GnuCOBOL compiler can be configured through the customSettings object, under the cobol-wasm key. The following options are supported:

  • sourceFormat: the COBOL source format, free (the default) or fixed.
  • compileArgs: extra GnuCOBOL (cobc) flags.
  • cCompileArgs: extra Clang flags for the generated C.
  • args: the program's command-line arguments.
  • fileName: the name the source is compiled under (main.cob by default).

Example:

const config = {
  activeEditor: 'script',
  script: {
    language: 'cobol-wasm',
    content: '...',
  },
  customSettings: {
    'cobol-wasm': {
      sourceFormat: 'fixed',
    },
  },
};

Code Formatting​

Not currently supported.

Live Reload​

By default, new code changes are sent to the result page for re-evaluation without a full page reload. This behavior can be disabled by adding the code comment *> __livecodes_reload__ to the COBOL code, which forces a full page reload.

This comment can be added in the hiddenContent property of the editor for embedded playgrounds.

Example Usage​

IDENTIFICATION DIVISION.
PROGRAM-ID. INVOICE.
DATA DIVISION.
WORKING-STORAGE SECTION.
01 WS-RATE  PIC 9(3)V99 VALUE 25.50.
01 WS-HOURS PIC 9(3) VALUE 40.
01 WS-PAY   PIC 9(5)V99.
PROCEDURE DIVISION.
    COMPUTE WS-PAY = WS-RATE * WS-HOURS
    DISPLAY "Rate: " WS-RATE
    DISPLAY "Pay:  " WS-PAY
    STOP RUN.

Starter Template​

https://livecodes.io/?template=cobol-wasm

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