Chain Language

Chain is serial data description language.

Use #

• cui
• argument parser
• inter-application communication

Syntax #

For example, tiger 's cui is chain language.

tiger run --taskLocation 'abc' --taskName 'tiger_sample.yaml'

run is head.
--taskLocation 'abc' and --taskName 'tiger_sample.yaml' is option.
There is no example, -log is flag.

Chain contains only Head, Option, and Flag.

Head #

1. head position is the beginning.
2. head prefix is no hypen.
3. head is not empty.
4. head quantity is 0 or 1.
   • depending on your system, you may want to implement a default head.

Option #

1. option position is free.
2. option prefix is double-hypen.
3. option is not empty.
4. option quantity is 0 or more.
5. option value quantity is 0 or more.
   • In the above example, 'abc' and 'tiger_sample.yaml' is option value.
6. option value position is right behind option or right behind option value.
   • you can make a List by placing option value in a row.
   • example, --something 'a' 'b' 'c'
7. option value prefix is no hypen.

Flag #

1. flag position is free.
2. flag prefix is single-hypen.
3. flag is not empty.
4. flag quantity is 0 or more.

Include white space #

if you want to include white space in serial source, Please circle it with single or double quotation.
example: --something 'hello world'

Include quotation #

if you want to include single quotation in serial source, Please circle it with double quotation.
example: --something "abc'def'ghi"
if you want to include double quotation in serial source, Please circle it with single quotation.
example: --something 'abc"def"ghi'

Other #

Triple-hypen or more prefix

Valid as head or option value.
But, Not recommended.

Pass value that starts with a hyphen to option value

Impossible.

There is no shorthand for head, option, and flag

There is only one way to specify.

Code example #

import 'package:bpriver_chain/bpriver_chain.dart';

void main() {

    final source = 'a --b x -c --v -w --x x y z -z';

    final parseStringResult = Chain.parseString(source);
    if (parseStringResult is! Success<List<String>, ChainSyntaxException>) {
        print('parseString() is Failure');
        return;
    }

    final parseListResult = Chain.parseList(parseStringResult.wrapped);
    if (parseListResult is! Success<Chain, ChainSyntaxException>) {
        print('parseList() is Failure');
        return;
    };

    final Chain chain = parseListResult.wrapped;

    final headResult = chain.getHead();
    if (headResult is! Success<String, ChainExceptionB>) {
        print('headBox is Failure');
        return;
    }
    final head = headResult.wrapped;

    final optionResult = chain.getOptionAsSingleString('b');
    if (optionResult is! Success<String, ChainExceptionIJK>) {
        print('option is Failure');
        return;
    };

    final option = optionResult.wrapped;

    final flagResult = chain.isFlag('c');

    final flag = flagResult.wrapped;
    
    if (flag == false) {
        print('flag is Failure');
        return;
    }

    final multipleOptionResult = chain.getOptionAsMultiple('x');
    if (multipleOptionResult is! Success<ArgumentList<ValueArgument>, ChainExceptionIJ>) {
        print('multiple option is Failure');
        return;
    }
    final multipleOption = multipleOptionResult.wrapped.toPrimitive();

    print('head = ${head}');
    print('b option = ${option}');
    print('c flag = ${flag}');
    print('x option = ${multipleOption}');

    final List<String> optionList = [];

    for (final i in chain.optionList) {
        
        optionList.add(i.nameArgument.name);

    }

    print('option list = ${optionList}');
    
    final List<String> flagList = [];

    for (final i in chain.flagList) {

        flagList.add(i.nameArgument.name);
        
    }
    
    print('flag list = ${flagList}');

}