clark

• clark
  • What is clark?
  • Prerequisites
  • Installation
    • Install the package
    • Install the CLI
  • Getting started
    • Create a Reader
    • Create a Lexer
      • Available Options
    • Start the lexing progress
    • Collect the lexed Tokens
  • Usage of the CLI

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What is clark?

Clark is a simple command-lexing package designed for chat systems such as Discord, Teamspeak, or Telegram. It is therefore intended to facilitate the handling of user input and the parsing processes that follow.

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Prerequisites

To use a Go package such as clark, you must of course have Go installed on your system.

It is assumed that you have already worked with the Go environment. If this is not the case, see this page first.

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Installation

Install the package

To use clark as a Go package, you must have it installed on your current system. If this is not the case, run the command below.

go get -u github.com/lukasl-dev/clark

Install the CLI

Otherwise, if you want to use clark inside your terminal, you need to have it installed as well. If this is not the case, run the command below.

If you have no experience in this section, read this.

go get -u github.com/lukasl-dev/clark/cmd/clark

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Getting started

Create a Reader

As an example, we create a strings.Reader here.

reader := strings.NewReader("!help")

Create a Lexer

lex, err := clark.NewLexer(reader)

You can configure the lexer using the variadic options.

See available Options.

lex, err := clark.NewLexer(
  reader,
  lexing.Prefixes("!"), lexing.Labels("help", "play", "help me"),
)

// handle error

Available Options

Function	Description
lexing.Prefixes	Prefixes defines the prefixes used by the lexer.
lexing.Labels	Labels defines the labels used by the lexer.
lexing.PrefixIgnoreCase	PrefixIgnoreCase defines the prefixes case sensitivity.
lexing.LabelIgnoreCase	LabelIgnoreCase defines the labels case sensitivity.
lexing.SkipPrefix	SkipPrefix defines whether the prefix should be skipped.
lexing.SkipLabel	SkipLabel defines whether the label should be skipped.

Start the lexing progress

To execute the Lexer , lex.Lex() is executed as a goroutine. lex.Lex() reads the passed reader lexicographically until io.EOF and returns the lexed tokens.

go lex.Lex()

Collect the lexed Tokens

During reading tokens are sent to the token channel. This channel can be accessed via lex.Chan().

for token := range lex.Chan() {
// handle token
}

A Token has a Type and an optional value.

See supported types.

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Usage of the CLI