Merge pull request #345 from willow-ahrens/wma/merge_limits

import changes to limits

src/base/limits.jl

@@ -131,13 +131,15 @@ struct Limit{T} <: Number
 end
 
 limit(x::T, s) where {T} = Limit{T}(x, s)
-plus_eps(x) = limit(x, tiny_positive())
-minus_eps(x) = limit(x, tiny_negative())
+plus_eps(x)::Limit = limit(0, tiny_positive())
+minus_eps(x)::Limit = limit(x, tiny_negative())
 limit(x) = limit(x, tiny_zero())
+limit(x::Limit) = x 
 Limit{T}(x) where {T} = limit(T(x))
 drop_eps(x::Limit) = x.val
+drop_eps(x::Number) = x
 
-const Eps = plus_eps(Int8(0))
+const Eps = Finch.plus_eps(Int8(0))
 
 function Base.show(io::IO, x::Limit)
     print(io, "limit(", x.val, x.sign, ")")
@@ -149,19 +151,19 @@ function Base.show(io::IO, mime::MIME"text/plain", x::Limit)
 end
 
 #Core definitions for limit type
-Base.:(+)(x::Limit, y::Limit) = limit(x.val + y.val, x.sign + y.sign)
-Base.:(*)(x::Limit, y::Limit) = limit(x.val * y.val, x.val * y.sign + y.val * x.sign) 
-Base.:(-)(x::Limit, y::Limit) = limit(x.val - y.val, x.sign - y.sign)
-Base.:(<)(x::Limit, y::Limit) = x.val < y.val || (x.val == y.val && x.sign < y.sign)
-Base.:(<=)(x::Limit, y::Limit) = x.val < y.val || (x.val == y.val && x.sign <= y.sign)
-Base.:(==)(x::Limit, y::Limit) = x.val == y.val && x.sign == y.sign
-Base.isless(x::Limit, y::Limit) = x < y
+Base.:(+)(x::Limit, y::Limit)::Limit = limit(x.val + y.val, x.sign + y.sign)
+Base.:(*)(x::Limit, y::Limit)::Limit = limit(x.val * y.val, x.val * y.sign + y.val * x.sign) 
+Base.:(-)(x::Limit, y::Limit)::Limit = limit(x.val - y.val, x.sign - y.sign)
+Base.:(<)(x::Limit, y::Limit)::Bool = x.val < y.val || (x.val == y.val && x.sign < y.sign)
+Base.:(<=)(x::Limit, y::Limit)::Bool = x.val < y.val || (x.val == y.val && x.sign <= y.sign)
+Base.:(==)(x::Limit, y::Limit)::Bool = x.val == y.val && x.sign == y.sign
+Base.isless(x::Limit, y::Limit)::Bool = x < y
 Base.isinf(x::Limit) = isinf(x.val)
 Base.zero(x::Limit{T}) where {T} = limit(convert(T, 0))
 Base.min(x::Limit) = x
 Base.max(x::Limit) = x
-Base.:(+)(x::Limit) = x
-Base.:(-)(x::Limit) = limit(-x.val, -x.sign)
+Base.:(+)(x::Limit)::Limit = x
+Base.:(-)(x::Limit)::Limit = limit(-x.val, -x.sign)
 
 #Crazy julia multiple dispatch stuff don't worry about it
 limit_types = [Int8, Int16, Int32, Int64, Int128, UInt8, UInt16, UInt32, UInt64, UInt128, BigInt, Float32, Float64]
@@ -172,6 +174,10 @@ for S in limit_types
         Limit(i::$S) = Limit{$S}(i, tiny())
         (::Type{$S})(i::Limit{T}) where {T} = convert($S, i.val)
         Base.convert(::Type{$S}, i::Limit) = convert($S, i.val)
+        Base.:(+)(x::Limit, y::$S)::Limit = x + limit(y)
+        Base.:(+)(x::$S, y::Limit)::Limit = limit(x) + y
+        Base.:(-)(x::Limit, y::$S)::Limit = x - limit(y)
+        Base.:(-)(x::$S, y::Limit)::Limit = limit(x) - y
         Base.:(<)(x::Limit, y::$S) = x < limit(y)
         Base.:(<)(x::$S, y::Limit) = limit(x) < y
         Base.:(<=)(x::Limit, y::$S) = x <= limit(y)
@@ -180,13 +186,13 @@ for S in limit_types
         Base.:(==)(x::$S, y::Limit) = limit(x) == y
         Base.isless(x::Limit, y::$S) = x < limit(y)
         Base.isless(x::$S, y::Limit) = limit(x) < y
-        Base.max(x::$S, y::Limit) = max(limit(x), y)
-        Base.max(x::Limit, y::$S) = max(x, limit(y))
-        Base.min(x::$S, y::Limit) = min(limit(x), y)
-        Base.min(x::Limit, y::$S) = min(x, limit(y))
+        Base.max(x::$S, y::Limit)::Limit = max(limit(x), y)
+        Base.max(x::Limit, y::$S)::Limit = max(x, limit(y))
+        Base.min(x::$S, y::Limit)::Limit = min(limit(x), y)
+        Base.min(x::Limit, y::$S)::Limit = min(x, limit(y))
     end
 end
 
-Base.promote_rule(::Type{Limit{T}}, ::Type{Limit{S}}) where {T, S} = promote_type(T, S)
+Base.promote_rule(::Type{Limit{T}}, ::Type{Limit{S}}) where {T, S} = Limit(promote_type(T, S))
 Base.convert(::Type{Limit{T}}, i::Limit) where {T} = Limit{T}(convert(T, i.val), i.sign)
 Base.hash(x::Limit, h::UInt) = hash(typeof(x), hash(x.val, hash(x.sign, h)))