Make jpm configurable for environments like MinGW.

CHANGELOG.md

@@ -10,6 +10,10 @@ All notable changes to this project will be documented in this file.
 - Remove the `tarray` module. The functionality of typed arrays will be moved to an external module
   that can be installed via `jpm`.
 - Add `from-pairs` to core.
+- Add `JPM_OS_WHICH` environment variable to jpm to allow changing auto-detection behavior.
+- The flychecker will consider any top-level calls of functions that start with `define-` to
+  be safe to execute and execute them. This allows certain patterns (like spork/path) to be
+  better processed by the flychecker.
 
 ## 1.15.5 - 2021-04-25
 - Add `declare-headers` to jpm.

README.md

@@ -234,7 +234,7 @@ See the examples directory for some example janet code.
 ## Discussion
 
 Feel free to ask questions and join the discussion on the [Janet Gitter Channel](https://gitter.im/janet-language/community).
-Alternatively, check out [the #janet channel on Freenode](https://webchat.freenode.net/)
+Gitter provides Matrix and irc bridges as well.
 
 ## FAQ
 
@@ -246,8 +246,35 @@ will not. If your terminal does not support ANSI escape codes, run the REPL with
 the `-n` flag, which disables color output. You can also try the `-s` if further issues
 ensue.
 
-## Why Janet
+### Where is (favorite feature from other language)?
+
+It may exist, it may not. If you want to propose major language features, go ahead and open an issue, but
+they will likely by closed as "will not implement". Often, such features make one usecase simpler at the expense
+of 5 others by making the language more complicated.
+
+### Where is the example code?
+
+In the examples directory.
+
+### Is this a Clojure port?
+
+No. It's similar to Clojure superficially because I like Lisps and I like the asthetics.
+Internally, Janet is not at all like Clojure.
+
+### Are the immutable data structures (tuples and structs) implemented as hash tries?
+
+No. They are immutable arrays and hash tables. Don't try and use them like Clojure's vectors
+and maps, instead they work well as table keys or other identifiers.
+
+### Why can't we add (feature from Clojure) into the core?
+
+Usually, one of a few reasons:
+- Often, it already exists in a different form and the Clojure port would be redundant.
+- Clojure programs often generate a lot of garbage and rely on the JVM to clean it up.
+  Janet does not run on the JVM. We admittedly have a much more primitive GC.
+- We want to keep the Janet core small. With Lisps, usually a feature can be added as a library
+  without feeling "bolted on", especially when compared to ALGOL like languages.
+
+## Why is it called "Janet"?
 
 Janet is named after the almost omniscient and friendly artificial being in [The Good Place](https://en.wikipedia.org/wiki/The_Good_Place).
-
-<img src="https://raw.githubusercontent.com/janet-lang/janet/master/assets/janet-the-good-place.gif" alt="Janet logo" width="115px" align="left">

jpm

@@ -6,14 +6,21 @@
 # Basic Path Settings
 #
 
-# Windows is the OS outlier
-(def- is-win (= (os/which) :windows))
-(def- is-mac (= (os/which) :macos))
-(def- sep (if is-win "\\" "/"))
-(def- objext (if is-win ".obj" ".o"))
-(def- modext (if is-win ".dll" ".so"))
-(def- statext (if is-win ".static.lib" ".a"))
-(def- absprefix (if is-win "C:\\" "/"))
+# Allow changing the behavior via an environment variable
+(def- host-os (keyword (string/ascii-lower (os/getenv "JPM_OS_WHICH" (os/which)))))
+(defn- define-utils
+  []
+  (def is-win (= host-os :windows))
+  (defglobal 'is-win is-win)
+  (defglobal 'is-mac (= host-os :macos))
+  (def sep (if is-win "\\" "/"))
+  (defglobal 'sep sep)
+  (defglobal 'objext (if is-win ".obj" ".o"))
+  (defglobal 'modext (if is-win ".dll" ".so"))
+  (defglobal 'statext (if is-win ".static.lib" ".a"))
+  (defglobal 'absprefix (if is-win "C:\\" "/")))
+
+(define-utils)
 
 #
 # Defaults
@@ -58,6 +65,9 @@
 
 ###END###
 
+# Redefine utils in case the above section is overriden on some installs.
+(define-utils)
+
 (compwhen (not (dyn 'extra-lflags))
   (def- extra-lflags []))
 
@@ -370,7 +380,7 @@
 # flags needed for the janet binary and compiling standalone
 # executables.
 (def janet-lflags
-  (case (os/which)
+  (case host-os
     :macos ["-ldl" "-lm" ;thread-flags ;extra-lflags]
     :windows [;thread-flags ;extra-lflags]
     :linux ["-lm" "-ldl" "-lrt" ;thread-flags ;extra-lflags]

jpm.1

@@ -269,5 +269,30 @@ An optional path to a git executable to use to clone git dependencies. By defaul
 if you have a normal install of git.
 .RE
 
+.B JPM_OS_WHICH
+.RS
+Use this option to override the C compiler and build system auto-detection for the host operating system. For example, set this
+environment variable to "posix" to make sure that on platforms like MinGW, you will use GCC instead of MSVC. On most platforms, users will not need to
+set this environment variable. Set this to one of the following
+strings:
+.IP
+\- windows
+.IP
+\- macos
+.IP
+\- linux
+.IP
+\- freebsd
+.IP
+\- openbsd
+.IP
+\- netbsd
+.IP
+\- bsd
+.IP
+\- posix
+.RE
+
+
 .SH AUTHOR
 Written by Calvin Rose <calsrose@gmail.com>

src/boot/boot.janet

@@ -3315,7 +3315,11 @@
   [thunk source env where]
   (when (tuple? source)
     (def head (source 0))
-    (def safe-check (safe-forms head))
+    (def safe-check
+      (or
+        (safe-forms head)
+        (if (symbol? head)
+          (if (string/has-prefix? "define-" head) is-safe-def))))
     (cond
       # Sometimes safe form
       (function? safe-check)