Merge pull request #14 from thautwarm/refactor

WIP Refactor: A concise and maintainable implementation

Author: thautwarm

Project.toml

@@ -1,15 +1,16 @@
 name = "JuliaVariables"
 uuid = "b14d175d-62b4-44ba-8fb7-3064adc8c3ec"
 authors = ["thautwarm"]
-version = "0.1.4"
+version = "0.2.0"
 
 [deps]
-LegibleLambdas = "f1f30506-32fe-5131-bd72-7c197988f9e5"
 MLStyle = "d8e11817-5142-5d16-987a-aa16d5891078"
 NameResolution = "71a1bf82-56d0-4bbc-8a3c-48b961074391"
 
 [compat]
 julia = "1"
+MLStyle = "^0.3.1"
+NameResolution = "^0.1.3"
 
 [extras]
 Test = "8dfed614-e22c-5e08-85e1-65c5234f0b40"

Specification.md

@@ -0,0 +1,77 @@
+# Specification of Julia Scoping Rule
+
+`S` indicates the current scope.
+Some terminologies(as well as interfaces provided in NameResolution.jl) :
+- `LHS`: left-hide-side
+- `RHS`: right-hide-side
+- `pseudo scope`: a scope but does not introduce free variables in its parent scope. I don't know how to call it actually, `pseudo scope` is a tentative name.
+- `LOCAL`: to mark a symbol as **local**, instead of resolving it automatically
+- `GLOBAL`: to mark a symbol as **global**, instead of resolving it automatically
+
+## For Loop
+
+```julia
+for i = I, j in J
+    body
+end
+```
+
+`i` is LHS in in `S/for1`, `I` is RHS in `S`.
+
+`j` is LHS in `S/for1/for2`, `J` is RHS in `S/for1`.
+
+`body` is RHS in `S/for1/for2`.
+
+
+## Standalone Assignments
+
+```julia
+$f = a
+```
+
+If `$f` is a function calling expression, it's treated as `function $f; a end` . See [Function Definition](#Function Definition).
+
+Otherwise, all symbols(except heads of expressions) of `$f` are LHS in `S`, `a` is RHS in `S`.
+
+## Functions
+
+```julia
+function f(x::A{T}=default_value) where T
+    body
+end
+```
+
+- `f` is LHS in `S`(however the function name should be marked for further analysis, e.g., self recursions).
+
+There's a *pseudo* scope `S/mk-type-params`,
+
+- `T` in `where T` is LHS in `S/mk-type-params`.
+
+The requirement of a symbol in argument type annotations is from the scope `S/mk-type-params`.
+
+Say,
+- `T` in `f(x::A{T}=value)` is RHS in `S/mk-type-params`, and
+- `A` is RHS in `S/mk-type-params`(though we know `A` is from `S`, pseudo scope doesn't result in free variables).
+
+The function execution has the scope `S/mk-type-params/inner` and,
+- `x` is LHS in `S/mk-type-params/inner`,
+- `default_value` is RHS in `S/mk-type-params/inner`,
+- `body` is RHS in `S/mk-type-params/inner`
+
+
+Except for
+- `Expr(:function, ::Symbol, Expr(:block, _...))` is a declaration
+
+## Let-Bindings
+
+```julia
+let a = b
+    c
+end
+```
+
+`S/let` is a pseudo scope.
+
+- `b` is RHS in `S`
+- `a` is LHS in `S/let`
+- `c` is RHS in `S/let`