From d7235837e1926cc6dd291959c6b3315abce26c04 Mon Sep 17 00:00:00 2001
From: Tortar <68152031+Tortar@users.noreply.github.com>
Date: Wed, 19 Jul 2023 12:54:11 +0200
Subject: [PATCH 1/5] Allow using default values in agents macro

---
 src/core/agents.jl | 14 +++++++++++++-
 1 file changed, 13 insertions(+), 1 deletion(-)

diff --git a/src/core/agents.jl b/src/core/agents.jl
index e8b48345c4..d47eb9cd33 100644
--- a/src/core/agents.jl
+++ b/src/core/agents.jl
@@ -91,6 +91,18 @@ mutable struct Baker{T} <: AbstractAgent
     breadz_per_day::T
 end
 ```
+Notice that you can also use default values for some fields, in this case you 
+will need to specify the field names with the non-default values
+```julia
+@agent Person{T} GridAgent{2} begin
+    age::Int = 30
+    moneyz::T
+end
+# default age value
+Person(id = 1, pos = (1, 1), moneyz = 2000)
+# new age value
+Person(1, (1, 1), 40, 2000)
+```
 ### Example with optional hierarchy
 An alternative way to make the above structs, that also establishes
 a user-specific subtyping hierarchy would be to do:
@@ -192,7 +204,7 @@ macro agent(new_name, base_type, super_type, extra_fields)
             expr = quote
                 # Also notice that we escape supertype and interpolate it twice
                 # because this is expected to already be defined in the calling module
-                mutable struct $name <: $$(esc(super_type))
+                @kwdef mutable struct $name <: $$(esc(super_type))
                     $(base_fields...)
                     $(additional_fields...)
                 end

From 83a732604060653b79c78bc87be1d5782b46dc47 Mon Sep 17 00:00:00 2001
From: Tortar <68152031+Tortar@users.noreply.github.com>
Date: Wed, 19 Jul 2023 12:56:30 +0200
Subject: [PATCH 2/5] Update model_creation_tests.jl

---
 test/model_creation_tests.jl | 7 +++++++
 1 file changed, 7 insertions(+)

diff --git a/test/model_creation_tests.jl b/test/model_creation_tests.jl
index ea12ab26dd..bb0ff1c289 100644
--- a/test/model_creation_tests.jl
+++ b/test/model_creation_tests.jl
@@ -35,6 +35,13 @@ using Test, Agents, Random
     end
     @test Fisher <: AbstractHuman
     @test :fish_per_day ∈ fieldnames(Fisher)
+
+    agent_kwdef = Agent9(id = 1, f2 = 10)
+    values = (1, 40, 10, 3.0)
+    @test all(getfield(agent_kwdef, n) == v for (n, v) in zip(fieldnames(Agent9), values))
+    agent_kwdef = Agent9(1, 20, 10, 4.0)
+    values = (1, 20, 10, 4.0)
+    @test all(getfield(agent_kwdef, n) == v for (n, v) in zip(fieldnames(Agent9), values))
 end
 
 

From b6a315a569ea48c6199c3a8de56db82c46c73787 Mon Sep 17 00:00:00 2001
From: Tortar <68152031+Tortar@users.noreply.github.com>
Date: Wed, 19 Jul 2023 12:56:54 +0200
Subject: [PATCH 3/5] Update runtests.jl

---
 test/runtests.jl | 6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/test/runtests.jl b/test/runtests.jl
index c14cbc631e..e75ab0e183 100644
--- a/test/runtests.jl
+++ b/test/runtests.jl
@@ -71,6 +71,12 @@ end
 
 Agent8(id, pos; f1, f2) = Agent8(id, pos, f1, f2)
 
+@agent Agent9 NoSpaceAgent begin
+    f1::Int = 40
+    f2::Int
+    f3::Float64 = 3.0
+end
+
 @agent SchellingAgent GridAgent{2} begin
     mood::Bool
     group::Int

From 9583dbcf7b769eaa738649d757c2e7c4e7416b37 Mon Sep 17 00:00:00 2001
From: Tortar <68152031+Tortar@users.noreply.github.com>
Date: Wed, 19 Jul 2023 13:01:00 +0200
Subject: [PATCH 4/5] Update agents.jl

---
 src/core/agents.jl | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/src/core/agents.jl b/src/core/agents.jl
index d47eb9cd33..264893f014 100644
--- a/src/core/agents.jl
+++ b/src/core/agents.jl
@@ -29,8 +29,8 @@ as well as any additional ones the user may provide via the `begin` block.
 See below for examples.
 
 Using `@agent` is the recommended way to create agent types for Agents.jl,
-however keep in mind that the macro (currently) doesn't work with `Base.@kwdef`
-or `const` declarations in individual fields (for Julia v1.8+).
+however keep in mind that the macro (currently) doesn't work with `const` 
+declarations in individual fields (for Julia v1.8+).
 
 Structs created with `@agent` by default subtype `AbstractAgent`.
 They cannot subtype each other, as all structs created from `@agent` are concrete types

From c559ed2fa1df3681ea9dfab8c43d07da4b9978a7 Mon Sep 17 00:00:00 2001
From: Tortar <68152031+Tortar@users.noreply.github.com>
Date: Wed, 19 Jul 2023 13:04:43 +0200
Subject: [PATCH 5/5] Update CHANGELOG.md

---
 CHANGELOG.md | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/CHANGELOG.md b/CHANGELOG.md
index a7e361364c..98935a9291 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -1,3 +1,7 @@
+# main
+
+- The `@agents` macro now supports fields with default values.
+
 # v5.17
 
 - New function `replicate!` allows to create a new instance of a given agent at the same position with the possibility to specify some