Hasse diagram contains a deep copy of the poset

README.md

@@ -4,7 +4,10 @@ Drawings of [Posets](https://github.com/scheinerman/Posets.jl) (partially ordere
 
 ## Basic Usage
 
+To create a Hasse diagram for a `Poset` and draw it on the screen, do this:
 ```
+julia> using Posets, HasseDiagrams
+
 julia> p = subset_lattice(3)
 {8, 19} Int64 poset
 
@@ -13,6 +16,7 @@ Hasse diagram of a {8, 19} Int64 poset
 
 julia> draw(h)
 ```
+Note that `h` contains a copy of `p`, so subsequent changes to `p` are not reflected in `h`.
 
 ## Creating a Layout
 

docs/build/.documenter-siteinfo.json

@@ -1 +1 @@
-{"documenter":{"julia_version":"1.10.5","generation_timestamp":"2024-09-02T15:15:13","documenter_version":"1.6.0"}}
+{"documenter":{"julia_version":"1.10.5","generation_timestamp":"2024-09-03T17:15:22","documenter_version":"1.6.0"}}

docs/src/index.md

@@ -4,7 +4,10 @@ Drawings of [Posets](https://github.com/scheinerman/Posets.jl) (partially ordere
 
 ## Basic Usage
 
+To create a Hasse diagram for a `Poset` and draw it on the screen, do this:
 ```
+julia> using Posets, HasseDiagrams
+
 julia> p = subset_lattice(3)
 {8, 19} Int64 poset
 
@@ -13,6 +16,7 @@ Hasse diagram of a {8, 19} Int64 poset
 
 julia> draw(h)
 ```
+Note that `h` contains a copy of `p`, so subsequent changes to `p` are not reflected in `h`.
 
 ## Creating a Layout
 

src/HasseDiagrams.jl

@@ -49,7 +49,7 @@ mutable struct HasseDiagram
             labels[v] = v
         end
 
-        return new(p, xy, RADIUS, FILL_COLOR, labels, FONT_SIZE)
+        return new(deepcopy(p), xy, RADIUS, FILL_COLOR, labels, FONT_SIZE)
     end
 end