comonicon · Roger-luo · Mar 4, 2022 · Mar 4, 2022 · Mar 4, 2022
diff --git a/src/Comonicon.jl b/src/Comonicon.jl
@@ -15,6 +15,7 @@ export @cast, @main, cmd_error, cmd_exit
 include("compat.jl")
 include("configs.jl")
 include("exceptions.jl")
+include("argtypes.jl")
 include("ast/ast.jl")
 include("codegen/julia.jl")
 include("codegen/zsh.jl")

diff --git a/src/argtypes.jl b/src/argtypes.jl
@@ -0,0 +1,70 @@
+module Arg
+
+export FileName, DirName,
+    UserName, Path, Prefix, Suffix,
+    @Prefix_str, @Suffix_str
+
+abstract type ArgType end
+
+struct Path <: ArgType
+    content::String
+end
+
+struct DirName <: ArgType
+    content::String
+end
+
+struct FileName <: ArgType
+    content::String
+end
+
+struct UserName <: ArgType
+    content::String
+end
+
+struct Prefix{name} <: ArgType
+    content::String
+end
+
+struct Suffix{name} <: ArgType
+    content::String
+end
+
+macro Prefix_str(s::String)
+    return Prefix{Symbol(s)}
+end
+
+macro Suffix_str(s::String)
+    return Suffix{Symbol(s)}
+end
+
+Base.show(io::IO, x::Prefix{name}) where name = print(io, "Prefix\"", name, "\"")
+Base.show(io::IO, x::Suffix{name}) where name = print(io, "Suffix\"", name, "\"")
+
+# use rust-like enum instead?
+# @renum ArgType begin
+#     Path
+#     DirName
+#     FileName
+#     UserName
+#     Prefix(name::String)
+#     AnyType(name::String)
+# end
+
+function Base.tryparse(::Type{T}, s::AbstractString) where {T <: ArgType}
+    return T(s)
+end
+
+function Base.tryparse(::Type{Prefix{name}}, s::AbstractString) where {name}
+    prefix = string(name)
+    startswith(s, prefix) && return Prefix{name}(s[length(prefix)+1:end])
+    return
+end
+
+function Base.tryparse(::Type{Suffix{name}}, s::AbstractString) where {name}
+    suffix = string(name)
+    endswith(s, suffix) && return Suffix{name}(s[1:end-length(suffix)])
+    return
+end
+
+end
diff --git a/src/ast/ast.jl b/src/ast/ast.jl
@@ -1,6 +1,9 @@
 module AST
 
-export ComoniconExpr, Description, LeafCommand, NodeCommand, Entry, Argument, Option, Flag, print_cmd
+export ComoniconExpr,
+    Description,
+    LeafCommand, NodeCommand,
+    Entry, Argument, Option, Flag, print_cmd
 
 include("types.jl")
 include("printing.jl")

diff --git a/test/argtype.jl b/test/argtype.jl
@@ -0,0 +1,8 @@
+using Test
+using Comonicon: Arg
+
+@testset "tryparse(::ArgType, s)" begin
+    @test tryparse(Arg.Path, "random-string").content == "random-string"
+    @test tryparse(Arg.Prefix"file-", "file-content").content == "content"
+    @test tryparse(Arg.Suffix".py", "script.py").content == "script"    
+end
diff --git a/test/runtests.jl b/test/runtests.jl
@@ -10,6 +10,10 @@ end
     include("options.jl")
 end
 
+@testset "argtype" begin
+    include("argtype.jl")
+end
+
 @testset "ast" begin
     include("ast/ast.jl")
 end