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Learning wdl (programming language)

I know very little about the wdl programming language. I currently don't intend to go very far with the language. This document will go over all of my knowledge of the wdl programming language.

Hello World in wdl

This is how you make a Hello World program in wdl:

echo "Hello World"

/!\ This example has not been tested yet, and may not work

Comments in wdl

Comments in wdl are the same as in languages like Shell.

Single line comments

Single line comments in wdl are written like so:

# This is a single line comment

Multi-line comments

I don't know if wdl supports multi-line comments.

Break keyword in wdl

wdl does not seem to support the break keyword.

Defining a workflow in wdl

wdl is a language used for creating workflows. A simple workflow can be created like so:

workflow simpleWorkflow {
  call WriteGreeting
}
task WriteGreeting {
    echo "Hello, WDL"
}

/!\ This example has not been tested yet, and may not work

Defining a task in wdl

Tasks are crucial for creating workflows. A task can be created like so:

task WriteGreeting {
    echo "Hello, WDL"
}

/!\ This example has not been tested yet, and may not work

Version shebang in wdl

wdl programs can be defined with the version of the wdl language being used. This can be done like so:

version 1.0
task WriteGreeting {
    echo "Hello, WDL"
}

/!\ This example has not been tested yet, and may not work

Other knowledge of the wdl programming language

1. wdl is a language by an unknown developer

2. wdl is not a semicolon and curly bracket language, but it is a curly bracket language

3. wdl uses the *.wdl file extension by default. I don't know if it uses any other file extensions.

4. wdl is written in all lower-case.

5. wdl is a command language.

6. Several major projects use wdl, including Microsoft.

7. wdl is not one of the top 50 programming languages (as of 2022, July 31st, it has never ranked 50 or higher on the TIOBE index)

8. wdl is a language recognized by GitHub (as of 2022, Tuesday, August 2nd)

9. No other knowledge of the wdl programming language

Additional comments

1. There aren't too many good sources online for the language, so it was harder to learn

2. No other additional comments available

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File info

File type: Markdown document (*.md *.mkd *.mdown *.markdown)

File version: 1 (2022, Tuesday, August 2nd at 3:25 pm PST)

Line count (including blank lines and compiler line): 167

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File history

Click/tap here to expand/collapse the history for this file

Version 1 (2022, Tuesday, August 2nd at 3:25 pm PST)

Changes:

• Started the file

• Added the title section

• Added the Hello World in wdl section

• Added the Comments in wdl section

• Added the Single line comments subsection

• Added the Multi-line comments subsection

• Added the break keyword in wdl section

• Added the Defining a workflow in wdl section

• Added the Defining a task in wdl section

• Added the Version shebang in wdl section

• Added the other knowledge of the wdl programming language section

• Added the Additional comments section

• Added the file info section

• Added the file history section

• No other changes in version 1

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