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diff --git a/node_modules/generate-function/README.md b/node_modules/generate-function/README.md new file mode 100644 index 0000000..97419e9 --- /dev/null +++ b/node_modules/generate-function/README.md @@ -0,0 +1,89 @@ +# generate-function + +Module that helps you write generated functions in Node + +``` +npm install generate-function +``` + +[![build status](http://img.shields.io/travis/mafintosh/generate-function.svg?style=flat)](http://travis-ci.org/mafintosh/generate-function) + +## Disclamer + +Writing code that generates code is hard. +You should only use this if you really, really, really need this for performance reasons (like schema validators / parsers etc). + +## Usage + +``` js +const genfun = require('generate-function') +const { d } = genfun.formats + +function addNumber (val) { + const gen = genfun() + + gen(` + function add (n) {') + return n + ${d(val)}) // supports format strings to insert values + } + `) + + return gen.toFunction() // will compile the function +} + +const add2 = addNumber(2) + +console.log('1 + 2 =', add2(1)) +console.log(add2.toString()) // prints the generated function +``` + +If you need to close over variables in your generated function pass them to `toFunction(scope)` + +``` js +function multiply (a, b) { + return a * b +} + +function addAndMultiplyNumber (val) { + const gen = genfun() + + gen(` + function (n) { + if (typeof n !== 'number') { + throw new Error('argument should be a number') + } + const result = multiply(${d(val)}, n + ${d(val)}) + return result + } + `) + + // use gen.toString() if you want to see the generated source + + return gen.toFunction({multiply}) +} + +const addAndMultiply2 = addAndMultiplyNumber(2) + +console.log(addAndMultiply2.toString()) +console.log('(3 + 2) * 2 =', addAndMultiply2(3)) +``` + +You can call `gen(src)` as many times as you want to append more source code to the function. + +## Variables + +If you need a unique safe identifier for the scope of the generated function call `str = gen.sym('friendlyName')`. +These are safe to use for variable names etc. + +## Object properties + +If you need to access an object property use the `str = gen.property('objectName', 'propertyName')`. + +This returns `'objectName.propertyName'` if `propertyName` is safe to use as a variable. Otherwise +it returns `objectName[propertyNameAsString]`. + +If you only pass `gen.property('propertyName')` it will only return the `propertyName` part safely + +## License + +MIT |