I'm little confused by various terminologies used in the SystemJS configuration. It talks about module, location, package etc...
Isn't module in JS is a single file, and package is a collection of modules or files? If so, how a module can be an alias to a package?
This is from the documentation page:
The map option is similar to paths, but acts very early in the normalization process. It allows you to map a module alias to a location or package:
Yes module is a single file, in javascript it's just the file name (with assumed .js extension) in quotes after from keyword in
import ... from 'some-module';
In SystemJS config file, paths and map can be used to define what actual file or URL that some-module refers to.
packages in config file allow you to apply a set of configuration parameters (default extension, module format, custom loader etc) for all modules in or below particular location (the key in packages object).
One of the settings in packages is main, which is similar to main in package.json in node (except that it's default value is empty, not index.js): it determines which file is loaded when the package location itself appears in from in import statement.
So, I think "how a module can be an alias to a package?" question about this
The map option is similar to paths, but acts very early in the
normalization process. It allows you to map a module alias to a
location or package:
can be explained on this example:
paths: {
'npm:': 'node_modules/'
},
map: {
'some-module': 'npm:some-module'
},
packages: {
'some-module': {
main: './index.js'
}
}
when these map, packages and path settings are applied by SystemJS to
import something from 'some-module';
they will cause SystemJS to load a module from node_modules/some-module/index.js under baseURL.
and
import something from 'some-module/subcomponent';
is mapped to node_modules/some-module/subcomponent.js.
Note: this is based on my experience with SystemJS 0.19. I haven't tried 0.20 yet.
Related
I'm getting this error:
Unknown plugin "transform-class-properties" specified in "base" at 0, attempted to resolve relative to "/home/me/Projects/myproj/src"
The message is pretty clear, so I know why it's happening, but I want to change where Babel looks for the plugins/presets/packages.
I'm using Babel with rollup via rollup-plugin-babel.
The options I'm giving it are:
{ plugins: [ 'transform-class-properties', 'transform-object-rest-spread' ],
babelrc: false }
However, I can't find an option to change where Babel looks for the plugins. Is there no way to do this without rewriting my plugins list to use absolute paths?
I also can't find a public API method for extracting the dependencies from .babelrc, so it's pretty hard to manually rewrite the file to use full paths. N.B. Babel configs might also be stored in package.json, and there's been some talk about adding support for .babelrc.js too -- I really don't want to maintain my own project that searches for all the different places a babel config might be hiding, parse the file(s), and scan it for all the plugins, with and without the arbitrary babel-plugin- prefixes.
You can use NODE_PATH to do the same.
$ npx babel test.js
Unknown plugin "external-helpers" specified in "/Users/tarun.lalwani/Desktop/babeltest/.babelrc" at 0, attempted to resolve relative to "/Users/tarun.lalwani/Desktop/babeltest"
After specifying the path for modules in a different location
$ NODE_PATH=/Users/tarun.lalwani/Desktop/babeltest2/node_modules npx babel test.js
function test() {
this.abc = function (url) {
return console.log(url);
};
}
NODE_PATH environment variable allows you to specify additional locations where the modules can be searched for
I'm trying to build a Swift Package Manager system package (a module.modulemap)
making available two system C libraries where one includes the other.
That is, one (say libcurl) is a base module and the other C library is including
that (like so: #include "libcurl.h"). On the regular C side this works, because
the makefiles pass in proper -I flags and all is good (and I could presumably
do the same in SPM, but I'd like to avoid extra flags to SPM).
So what I came up with is this module map:
module CBase [system] {
header "/usr/include/curl.h"
link "curl"
export *
}
module CMyLib [system] {
use CBase
header "/usr/include/mylib.h"
link "mylib"
export *
}
I got importing CBase in a Swift package working fine.
But when I try to import CMyLib, the compiler complains:
error: 'curl.h' file not found
Which is kinda understandable because the compiler doesn't know where to look
(though I assumed that use CBase would help).
Is there a way to get this to work w/o having to add -Xcc -I flags to the
build process?
Update 1: To a degree this is covered in
Swift SR-145
and
SE-0063: SwiftPM System Module Search Paths.
The recommendation is to use the Package.swift pkgConfig setting. This seems to work OK for my specific setup. However, it is a chicken and egg if there is no .pc file. I tried embedding an own .pc file in the package, but the system package directory isn't added to the PKG_CONFIG_PATH (and hence won't be considered during the compilation of a dependent module). So the question stands: how to accomplish that in an environment where there libs are installed, but w/o a .pc file (just header and lib).
I have a Swift library with a core module plus optional bonus modules. I would like to use the following directory layout, mapping to exported Swift package names as shown:
Taco/
Source/
Core/ → import Taco
Toppings/ → import TacoToppings
SideDishes/ → import TacoSideDishes
To my eyes, that’s a sensible-looking project layout. However, if I’m reading the docs right, this will pollute the global module namespace with unhelpful names like “Core”. It seems that SwiftPM will only export a module whose name is identical to the directory name, and thus I have to do this:
Taco/
Source/
Taco/
TacoToppings/
TacoSideDishes/
Is there a way to configure Package.swift to use the tidier directory layout above and still export the desired module names?
Alternatively, is it possible to make the Core, Toppings, and SideDishes modules internal to the project, and export them all to the world as one big Taco module?
There is not currently a clean way to do this, but it seems like a reasonable request. I recommend filing an enhancement request at http://bugs.swift.org for it.
There is one "hacky" way you can do this:
Create your sources in the desired internal layout:
Sources/Core
Sources/Toppings
Add additional symbolic links for the desired module names:
ln -s Core Sources/Taco
ln -s Toppings Sources/TacoToppings
Add an exclude directive to the manifest to ignore the non-desired module name:
let package = Package(
name: "Taco",
exclude: ["Sources/Core", "Sources/Toppings"]
)
is it possible to make the Core, Toppings, and SideDishes modules internal to the project, and export them all to the world as one big Taco module?
No, unfortunately there is no way to do this currently, and it requires substantial compiler work to be able to support.
I would like use TypeScript.NET in my angular application. I am newbie in typescript and maybe root of problem is simple.
For example I would like to use StringBuilder.
First I install TypeScript via nuget
Add ref to index.html
<script src="source/System/Text/StringBuilder.js"></script>
<script src="source/System/Text/Utility.js"></script>
Here I am confuse, I don’t use any module system (e.g commonJs, amd, etc).
TypeScript.NET nuget add to my project folder dist which constains probably dist version for amd, commonjs etc hence I reference files from source folder.
Now I want to use StringBuilder in my internal module.
module App.Company{
//in internal module
import IVersion = App.IVersion;
import IError = App.IError;
//TypeScript.NET
import StringBuilder from "../../../../source/system/text/stringbuilder";
}
Here I get compilation errror
Import declarations in a namespace cannot reference a module
What is solution?
Second how can simple reference all types from TypeScript.NET?
I can't use functions of custom subdirectories.
My Code Organziation
I have under "src" a path hierarchy like
a/b
with all my directories and go-Files (it is the "root" of my project). The directories contain no subdirectories and it works fine. So the deepest path is "a/b/c". E.g. I have
a/b/c
and
a/b/d
with some go-files. Import of "a/b/d" and calling a function with "d.DoSomething()" from a file in "a/b/c" works fine.
Problem description
Now I want ot reorganize "a/b/d". I move some files from "a/b/d" to
a/b/d/e
and the rest of the files to
a/b/d/f
If try to import "a/b/d/e" with import-statement
import ( "a/b/d/e" )
from the same file in "/a/b/c" and want to call "e.DoSomething()" (it is the place, where the file with the "DoSomething-function" moved to), I get an error at the line, where I call "e.DoSomething()": "undefined: e".
While searching for a result, I've nowhere seen examples with deeper path hierarchies. Is it generally not possible to use/import subdirectories or what's the problem?
go-version I used: go1.2.2 linux/amd64
Thanks for any advices
Your approach is completely wrong. Go has absolutely no concept of importing files or directories, all you can import in Go are packages. It now happens that the name of a package is it's path relative to GOPATH and you import packages by that name. But the identifier under which an imported package is available in the importing code depends on the package declaration of the package. You cannot simply "move" files between directories as each directory (for the go tool) is a single package without changing the package declaration.
You can have package x under path a/b/c. When you import package x with import ( "a/b/c" ) all the exported stuff from package x is available to you as x.ExportedName.
Please read http://blog.golang.org/organizing-go-code carefully.
Try and do a go build in a/b/d/e first, before trying to build in a/b: that will generate the compiled classes you want to import.