Why does this constructor not work with 1 Int parameter?

Hi all,

I am new to Julia and am experimenting with trying to create compact code. I created the following types:

module Types

export Percentage

struct Percentage <: Real
    value::Float64
    Percentage(x) = x < 0 ? 0 : x > 1 ? 1 : new(round(x, digits = 6))
end

Base.show(io::IO, x::Percentage) = print(io, "$(x.value * 100)%")

Base.convert(::Type{Percentage}, x::Real) = Percentage(x)
Base.convert(::Type{Percentage}, x::Percentage) = x

Base.promote_rule(::Type{T}, ::Type{Percentage}) where T <: Real = Percentage

import Base: +, -, <, >, <=, >=, ==

+(x::Percentage, y::Percentage) = Percentage(x.value + y.value)
-(x::Percentage) = Percentage(-x.value)
-(x::Percentage, y::Percentage) = Percentage(x.value - y.value)
<(x::Percentage, y::Percentage) = x.value < y.value
<=(x::Percentage, y::Percentage) = x.value <= y.value
>(x::Percentage, y::Percentage) = x.value > y.value
>=(x::Percentage, y::Percentage) = x.value >= y.value
==(x::Percentage, y::Percentage) = x.value == y.value

Base.max(x::Percentage, y::Percentage) = Percentage(max(x.value, y.value))
Base.min(x::Percentage, y::Percentage) = Percentage(min(x.value, y.value))

end

abstract type Longevity end

struct Mechanical <: Longevity
    health::Percentage
    damage_thresholds::Vector{Tuple{Percentage, Float64}}
    repair_thresholds::Vector{Tuple{Percentage, Float64}}
end

Mechanical(
    health::Real = 1;
    damage_thresholds::Vector{Tuple{Percentage,Real}} = Vector(),
    repair_thresholds::Vector{Tuple{Percentage,Real}} = Vector(),
) = Mechanical(Percentage(health), damage_thresholds, repair_thresholds)

I tried to use the Mechanical constructor with an Int
Mechanical(1)
expecting that the int would call the Percentage() constructor and the rest of the parameters would be set to their default values. Instead I get the following error:

ERROR: MethodError: no method matching #Mechanical#10(::Array{Any,1}, ::Array{Any,1}, ::Type{Mechanical}, ::Int64)
Closest candidates are:
  #Mechanical#10(::Array{Tuple{Percentage,Real},1}, ::Array{Tuple{Percentage,Real},1}, ::Type{Mechanical}, ::Real) at /Users/stef/Programming/Julia Projects/Simulation Cockpit/cockpit/Entities.jl:35
Stacktrace:
 [1] Mechanical(::Int64) at /Users/stef/Programming/Julia Projects/Simulation Cockpit/cockpit/Entities.jl:35
 [2] top-level scope at none:1

I’m completely confused with the suggested constructor since the order of the parameters looks completely out of whack. I guess I’m missing something but I don’t know what to be honest.

Thanks in advance,
Stef

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