pluck

• pluck is a modular and composable programming language construction kit.
• Get started with WebAssembly text format syntax and macros.
• Create and use macros to construct your own programming language features.
• Additional project documentation is hosted at Notion.

Create a macro to recognize and transpile integer values to WebAssembly

enter : function(node, index, parents, state) {
  
  if (! shared.is_inside_function(state)) return
  if (! query.is_type(node, 'number')) return
  let parent = query.last(parents)
  if (query.is_type_value(parent.value[0], 'symbol', 'i32.const')) return
  if (query.is_type_value(parent.value[0], 'symbol', 'br')) return
  if (query.is_type_value(parent.value[0], 'symbol', 'br_if')) return
  parent.value[index] = parse(` (i32.const ${node.value})`)[0]
}

Create a macro to configure function parameters

enter : function(node, index, parents, state) {
  
  let parent = query.last(parents)
  if (! query.is_type(parent, 'expression')) return
  if (! query.is_length_exceeding(parent, 2)) return
  if (! query.is_type_value(parent.value[0], 'symbol', 'func')) return
  if (! query.is_type_value(parent.value[2], 'symbol', 'accepts')) return
  iterate(state.func.value, function(each, index) {
    if (index <= 2) return true
    if (query.is_type(each, 'expression')) return false
    if (query.is_type(each, 'whitespace')) return true			// whitespace should be folded already but encountered an issue anyway
    let value = shared.dollarize(each.value)
    parent.value[index] = parse(` (param ${value} i32)`)[0]
    return true
  })
  parent.value.splice(2, 1)
  parent.emit('removed', 2)
  state.locals = shared.find_locals(state)
}

Install your macros

macros: [
  ...
  require('./macros/accepts.js')
  require('./macros/number.js')
  ...
]

Write example code to use your new macros

module
  
  import "../library/utility.watm"
  import "../library/memory.watm"
  import "../library/string.watm"
  import "../library/number.watm"
  import "../library/boolean.watm"
  import "../library/types.watm"
  import "../library/console.watm"
  import "host" "table" (table 1 anyfunc)
  memory (import "host" "memory") 1
  
  func main
    
    memory_bootstrap
    callable 42
    
  func callable accepts value
    set input to value

Overview

• A work in process to get up and running quickly with WebAssembly text format.
• Parses WebAssembly .wat files, transforms using macros, and launches the project's main function.
• s-expressions in WebAssembly text format are parsed using a fork of the simple, tiny parser combinator library: uparse
  • https://github.com/jimf/uparse
• The parser infers s-expression statements from indentations in the source code.
• Transformations for string building and automatic module importing and exporting are included.
• Each module's functions are exported automatically using macros.
• Each module's functions are imported automatically using macros.
• Several macros have been partially implemented such as: repeat, if, break, function references, and some logic and arithmetic operators.
• Contains the beginning of a basic standard library in WebAssembly text format.
  • strings, numbers, booleans, lists, maps, binary trees, assertions
• The parser supports documentation first.
  • Runnable wat source code can be compiled while embedded inside markdown documentation.

Structure

• /examples
• /macros
• /library
• /compiler
• /runtime
• /parser
• /browser
• /fixtures

Requirements

• Requires Node.js
• Tested with Node.js 13.10.1
• Node.js 10.16.3 seems to be missing WebAssembly.Global

Run with GitPod

Open pluck in GitPod.

git fetch && git fetch --tags
git checkout 2020-04-16
nvm install 13.10.1
nvm use 13.10.1
npm install
npm start index
npm start macros
npm start stress
npm start tiny
npm start compaction

Run locally

git clone https://github.com/simplygreatwork/pluck.git
cd pluck
git checkout 2020-04-16
nvm install 13.10.1
nvm use 13.10.1
npm install
npm start index
npm start macros

You can run any of the files in the examples folder. Here are some highlights:

npm start objects
npm start lists
npm start maps
npm start if
npm start if-else
npm start repeat
npm start repeat-if
npm start repeat-nested
npm start operators
npm start negation

You can also optionally clean, compile, and run. e.g.

npm start index --clean
npm start index --no-run
npm start index --no-compile
npm start index --clean --no-run

If you encounter any troubles compiling or running, use the option --clean or delete the build folder.