special case isoperator for ' with unicode suffix

JuliaLang · Sep 12, 2020 · 355a3da · 355a3da
1 parent 70a4071
commit 355a3da
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Showing 2 changed files with 32 additions and 3 deletions.
diff --git a/base/show.jl b/base/show.jl
@@ -1128,6 +1128,8 @@ function isidentifier(s::AbstractString)
 end
 isidentifier(s::Symbol) = isidentifier(string(s))
 
+is_op_suffix_char(c::AbstractChar) = ccall(:jl_op_suffix_char, Cint, (UInt32,), c) != 0
+
 """
     isoperator(s::Symbol)
 
@@ -1139,7 +1141,9 @@ julia> Base.isoperator(:+), Base.isoperator(:f)
 (true, false)
 ```
 """
-isoperator(s::Union{Symbol,AbstractString}) = ccall(:jl_is_operator, Cint, (Cstring,), s) != 0
+function isoperator(s::Union{Symbol,AbstractString})
+    return ccall(:jl_is_operator, Cint, (Cstring,), s) != 0 || ispostfixoperator(s)
+end
 
 """
     isunaryoperator(s::Symbol)
@@ -1166,7 +1170,26 @@ julia> Base.isbinaryoperator(:-), Base.isbinaryoperator(:√), Base.isbinaryoper
 (true, false, false)
 ```
 """
-isbinaryoperator(s::Symbol) = isoperator(s) && (!isunaryoperator(s) || is_unary_and_binary_operator(s))
+function isbinaryoperator(s::Symbol)
+    return isoperator(s) && !ispostfixoperator(s) &&
+        (!isunaryoperator(s) || is_unary_and_binary_operator(s))
+end
+
+"""
+    ispostfixoperator(s::Union{Symbol,AbstractString})
+
+Return `true` if the symbol can be used as a postfix operator, `false` otherwise.
+
+# Examples
+```jldoctest
+julia> Base.ispostfixoperator(Symbol("'")), Base.ispostfixoperator(Symbol("'ᵀ")), Base.ispostfixoperator(:-)
+(true, true, false)
+```
+"""
+function ispostfixoperator(s::Union{Symbol,AbstractString})
+    s = String(s)
+    return startswith(s, '\'') && all(is_op_suffix_char, SubString(s, 2))
+end
 
 """
     operator_precedence(s::Symbol)
@@ -1589,7 +1612,7 @@ function show_unquoted(io::IO, ex::Expr, indent::Int, prec::Int, quote_level::In
     elseif (head === Symbol("'") && nargs == 1) || (
         # ' with unicode suffix is a call expression
         head === :call && nargs == 2 && args[1] isa Symbol &&
-        occursin(r"^'[\p{Lm}]+$", string(args[1]))
+        ispostfixoperator(args[1]) && args[1] !== Symbol("'")
     )
         op, arg1 = head === Symbol("'") ? (head, args[1]) : (args[1], args[2])
         if isa(arg1, Expr) || (isa(arg1, Symbol) && isoperator(arg1))

diff --git a/test/show.jl b/test/show.jl
@@ -2009,3 +2009,9 @@ end
 
 @test sprint(show, :(a'ᵀ)) == ":(a'ᵀ)"
 @test sprint(show, :((+)')) == ":((+)')"
+for s in (Symbol("'"), Symbol("'⁻¹"))
+    @test Base.isoperator(s)
+    @test !Base.isunaryoperator(s)
+    @test !Base.isbinaryoperator(s)
+    @test Base.ispostfixoperator(s)
+end