Make juvix compile default to native target (#1502)

README.org

@@ -116,9 +116,7 @@ brew install --build-from-source --HEAD juvix --verbose
 
 ** The Hello World Example
 
-In the following example a Juvix file is compiled to Wasm. Please check out the documentation
-[[https://anoma.github.io/juvix/getting-started/dependencies.html][Installing
-dependencies]] for instructions on how to setup your environment for compiling Juvix. You can also run =juvix doctor= to check your system setup.
+This is the Juvix source code of the traditional Hello World program.
 
 #+begin_src shell
 -- HelloWorld.juvix
@@ -132,15 +130,26 @@ main ≔ putStrLn "hello world!";
 end;
 #+end_src
 
-Then, run the following commands at the location folder of the file =HelloWorld.juvix=:
+To compile and run a binary generated by Juvix, save the source code to a file
+called =HelloWorld.juvix= and run the following command from the directory
+containing it:
 
 #+begin_src shell
 juvix compile HelloWorld.juvix
-wasmer HelloWorld.wasm
+./HelloWorld
 #+end_src
 
 You should see the output: =hello world!=
 
+The source code can also be compiled to a WebAssembly binary. This requires some
+additional setup. See [[https://anoma.github.io/juvix/getting-started/dependencies.html][Installing dependencies]] in the documentation for more
+information. You can also run =juvix doctor= to check your setup.
+
+#+begin_src shell
+juvix compile --target wasm HelloWorld.juvix
+wasmer HelloWorld.wasm
+#+end_src
+
 ** The Juvix programming language
 
 Juvix allows us to write programs with a high degree of assurance. The Juvix

app/Commands/Compile.hs

@@ -36,7 +36,7 @@ parseCompile = do
       ( long "target"
           <> short 't'
           <> metavar "TARGET"
-          <> value TargetWasm
+          <> value TargetNative
           <> showDefaultWith targetShow
           <> help "select a target: wasm, c, native"
       )

docs/org/tutorials/nodejs-interop.org

@@ -37,7 +37,7 @@ end;
 The Juvix module can be compiled using the following command:
 
 #+begin_src
-juvix compile -r standalone NodeJsInterop.juvix
+juvix compile -t wasm -r standalone NodeJsInterop.juvix
 #+end_src
 
 This will create a file containing a Wasm module called =NodeJsInterop.wasm=.
@@ -55,7 +55,7 @@ The functions =ptrToCstr= and =cstrlen= are necessary to convert the =char=
 pointer passed from Juvix to a JS =String=.
 
 #+begin_src
--- NodeJSInterop.js
+// NodeJSInterop.js
 const fs = require('fs');
 let wasmModule = null;