diff options
Diffstat (limited to 'deps/npm/node_modules/node-gyp/node_modules/nopt/README.md')
| -rw-r--r-- | deps/npm/node_modules/node-gyp/node_modules/nopt/README.md | 211 |
1 files changed, 211 insertions, 0 deletions
diff --git a/deps/npm/node_modules/node-gyp/node_modules/nopt/README.md b/deps/npm/node_modules/node-gyp/node_modules/nopt/README.md new file mode 100644 index 0000000000..f21a4b31c5 --- /dev/null +++ b/deps/npm/node_modules/node-gyp/node_modules/nopt/README.md @@ -0,0 +1,211 @@ +If you want to write an option parser, and have it be good, there are +two ways to do it. The Right Way, and the Wrong Way. + +The Wrong Way is to sit down and write an option parser. We've all done +that. + +The Right Way is to write some complex configurable program with so many +options that you hit the limit of your frustration just trying to +manage them all, and defer it with duct-tape solutions until you see +exactly to the core of the problem, and finally snap and write an +awesome option parser. + +If you want to write an option parser, don't write an option parser. +Write a package manager, or a source control system, or a service +restarter, or an operating system. You probably won't end up with a +good one of those, but if you don't give up, and you are relentless and +diligent enough in your procrastination, you may just end up with a very +nice option parser. + +## USAGE + + // my-program.js + var nopt = require("nopt") + , Stream = require("stream").Stream + , path = require("path") + , knownOpts = { "foo" : [String, null] + , "bar" : [Stream, Number] + , "baz" : path + , "bloo" : [ "big", "medium", "small" ] + , "flag" : Boolean + , "pick" : Boolean + , "many1" : [String, Array] + , "many2" : [path] + } + , shortHands = { "foofoo" : ["--foo", "Mr. Foo"] + , "b7" : ["--bar", "7"] + , "m" : ["--bloo", "medium"] + , "p" : ["--pick"] + , "f" : ["--flag"] + } + // everything is optional. + // knownOpts and shorthands default to {} + // arg list defaults to process.argv + // slice defaults to 2 + , parsed = nopt(knownOpts, shortHands, process.argv, 2) + console.log(parsed) + +This would give you support for any of the following: + +```bash +$ node my-program.js --foo "blerp" --no-flag +{ "foo" : "blerp", "flag" : false } + +$ node my-program.js ---bar 7 --foo "Mr. Hand" --flag +{ bar: 7, foo: "Mr. Hand", flag: true } + +$ node my-program.js --foo "blerp" -f -----p +{ foo: "blerp", flag: true, pick: true } + +$ node my-program.js -fp --foofoo +{ foo: "Mr. Foo", flag: true, pick: true } + +$ node my-program.js --foofoo -- -fp # -- stops the flag parsing. +{ foo: "Mr. Foo", argv: { remain: ["-fp"] } } + +$ node my-program.js --blatzk -fp # unknown opts are ok. +{ blatzk: true, flag: true, pick: true } + +$ node my-program.js --blatzk=1000 -fp # but you need to use = if they have a value +{ blatzk: 1000, flag: true, pick: true } + +$ node my-program.js --no-blatzk -fp # unless they start with "no-" +{ blatzk: false, flag: true, pick: true } + +$ node my-program.js --baz b/a/z # known paths are resolved. +{ baz: "/Users/isaacs/b/a/z" } + +# if Array is one of the types, then it can take many +# values, and will always be an array. The other types provided +# specify what types are allowed in the list. + +$ node my-program.js --many1 5 --many1 null --many1 foo +{ many1: ["5", "null", "foo"] } + +$ node my-program.js --many2 foo --many2 bar +{ many2: ["/path/to/foo", "path/to/bar"] } +``` + +Read the tests at the bottom of `lib/nopt.js` for more examples of +what this puppy can do. + +## Types + +The following types are supported, and defined on `nopt.typeDefs` + +* String: A normal string. No parsing is done. +* path: A file system path. Gets resolved against cwd if not absolute. +* url: A url. If it doesn't parse, it isn't accepted. +* Number: Must be numeric. +* Date: Must parse as a date. If it does, and `Date` is one of the options, + then it will return a Date object, not a string. +* Boolean: Must be either `true` or `false`. If an option is a boolean, + then it does not need a value, and its presence will imply `true` as + the value. To negate boolean flags, do `--no-whatever` or `--whatever + false` +* NaN: Means that the option is strictly not allowed. Any value will + fail. +* Stream: An object matching the "Stream" class in node. Valuable + for use when validating programmatically. (npm uses this to let you + supply any WriteStream on the `outfd` and `logfd` config options.) +* Array: If `Array` is specified as one of the types, then the value + will be parsed as a list of options. This means that multiple values + can be specified, and that the value will always be an array. + +If a type is an array of values not on this list, then those are +considered valid values. For instance, in the example above, the +`--bloo` option can only be one of `"big"`, `"medium"`, or `"small"`, +and any other value will be rejected. + +When parsing unknown fields, `"true"`, `"false"`, and `"null"` will be +interpreted as their JavaScript equivalents. + +You can also mix types and values, or multiple types, in a list. For +instance `{ blah: [Number, null] }` would allow a value to be set to +either a Number or null. When types are ordered, this implies a +preference, and the first type that can be used to properly interpret +the value will be used. + +To define a new type, add it to `nopt.typeDefs`. Each item in that +hash is an object with a `type` member and a `validate` method. The +`type` member is an object that matches what goes in the type list. The +`validate` method is a function that gets called with `validate(data, +key, val)`. Validate methods should assign `data[key]` to the valid +value of `val` if it can be handled properly, or return boolean +`false` if it cannot. + +You can also call `nopt.clean(data, types, typeDefs)` to clean up a +config object and remove its invalid properties. + +## Error Handling + +By default, nopt outputs a warning to standard error when invalid values for +known options are found. You can change this behavior by assigning a method +to `nopt.invalidHandler`. This method will be called with +the offending `nopt.invalidHandler(key, val, types)`. + +If no `nopt.invalidHandler` is assigned, then it will console.error +its whining. If it is assigned to boolean `false` then the warning is +suppressed. + +## Abbreviations + +Yes, they are supported. If you define options like this: + +```javascript +{ "foolhardyelephants" : Boolean +, "pileofmonkeys" : Boolean } +``` + +Then this will work: + +```bash +node program.js --foolhar --pil +node program.js --no-f --pileofmon +# etc. +``` + +## Shorthands + +Shorthands are a hash of shorter option names to a snippet of args that +they expand to. + +If multiple one-character shorthands are all combined, and the +combination does not unambiguously match any other option or shorthand, +then they will be broken up into their constituent parts. For example: + +```json +{ "s" : ["--loglevel", "silent"] +, "g" : "--global" +, "f" : "--force" +, "p" : "--parseable" +, "l" : "--long" +} +``` + +```bash +npm ls -sgflp +# just like doing this: +npm ls --loglevel silent --global --force --long --parseable +``` + +## The Rest of the args + +The config object returned by nopt is given a special member called +`argv`, which is an object with the following fields: + +* `remain`: The remaining args after all the parsing has occurred. +* `original`: The args as they originally appeared. +* `cooked`: The args after flags and shorthands are expanded. + +## Slicing + +Node programs are called with more or less the exact argv as it appears +in C land, after the v8 and node-specific options have been plucked off. +As such, `argv[0]` is always `node` and `argv[1]` is always the +JavaScript program being run. + +That's usually not very useful to you. So they're sliced off by +default. If you want them, then you can pass in `0` as the last +argument, or any other number that you'd like to slice off the start of +the list. |