zig: deallocate a varargs function after applying it

impls/zig/Dockerfile

@@ -1,4 +1,4 @@
-FROM ubuntu:bionic
+FROM ubuntu:24.04
 MAINTAINER Joel Martin <[email protected]>
 
 ##########################################################
@@ -9,25 +9,18 @@ MAINTAINER Joel Martin <[email protected]>
 RUN apt-get -y update
 
 # Required for running tests
-RUN apt-get -y install make python
-
-# Some typical implementation and test requirements
-RUN apt-get -y install curl libreadline-dev libedit-dev libpcre3-dev
+RUN apt-get -y install make python3
+RUN ln -fs /usr/bin/python3 /usr/local/bin/python
 
 RUN mkdir -p /mal
 WORKDIR /mal
 
 ##########################################################
 # Specific implementation requirements
 ##########################################################
+RUN apt-get -y install ca-certificates curl gcc libc6-dev libpcre3-dev libreadline-dev xz-utils
 
-RUN apt-get -y install gcc gdc ldc gpg wget
-
-RUN wget https://ziglang.org/download/0.5.0/zig-linux-x86_64-0.5.0.tar.xz && \
-    echo `pwd`  && \
-    tar -xf zig-linux-x86_64-0.5.0.tar.xz && \
-    cp -r zig-linux-x86_64-0.5.0 /usr/local/bin && \
-    ln -sf /usr/local/bin/zig-linux-x86_64-0.5.0/zig /usr/local/bin/zig && \
-    chmod +x /usr/local/bin/zig
+RUN curl https://ziglang.org/download/0.13.0/zig-linux-x86_64-0.13.0.tar.xz | tar -xJC/opt
+RUN ln -fst/usr/local/bin /opt/zig-linux-x86_64-0.13.0/zig
 
 ENV HOME /mal

impls/zig/Makefile

@@ -3,14 +3,13 @@ STEPS = step0_repl step1_read_print step2_eval step3_env step4_if_fn_do step5_tc
 
 all: $(STEPS)
 
-dist: mal
+zig_opts += --release=safe
+zig_opts += -Doptimize=Debug
+$(STEPS):
+	zig build $(zig_opts) -Dname=$@ [email protected]
 
-
-%: %.zig
-	zig build -Drelease-fast=true
-	ln -sf zig-cache/bin/$* .
-
-.PHONY: clean
+.PHONY: all $(STEPS) clean
 
 clean:
-	rm -f $(STEPS)
+	rm -fr .zig-cache/ zig-out/
+	rm -f *~

impls/zig/README

@@ -0,0 +1,24 @@
+debug_alloc in types.zig may help with reference counting.
+
+
+TODO Simplify the printer with the new reader functions in the zig
+library.
+
+
+NOTE Before implementing any optimization or optional fix that would
+increase the complexity, please take into account that someone has to
+maintain the code, and the zig language evolves quickly.
+
+Some memory leaks are probably already present, especially when an
+error interrupts the normal execution flow.
+
+Examples of things that are deliberately not implemented...
+  * TCO for try*
+  * preallocate integers between 0 and 100 at startup
+  * use ArrayList.ensureTotalCapacityPrecise/HashMap.ensureTotalCapacity
+    after most calls to new_list/vector/map.
+  * store symbols in a global hash map,
+  * implement lists/vectors as slices/cons cells/whatever
+  * deallocate cyclic structures not detected by reference counting like
+    (let* (f (fn* () nil)))
+    (def! a (atom 2)) (def! v [a]) (reset! a v)

impls/zig/build.zig

@@ -1,35 +1,26 @@
-const LibExeObjStep = @import("std").build.LibExeObjStep;
-const Builder = @import("std").build.Builder;
-const builtin = @import("builtin");
-
-const warn = @import("std").debug.warn;
+const Builder = @import("std").Build;
 
 pub fn build(b: *Builder) void {
-    const mode = b.standardReleaseOptions();
 
-    const exes = [_] *LibExeObjStep {
-        b.addExecutable("step0_repl",       "step0_repl.zig"),
-        b.addExecutable("step1_read_print", "step1_read_print.zig"),
-        b.addExecutable("step2_eval",       "step2_eval.zig"),
-        b.addExecutable("step3_env",        "step3_env.zig"),
-        b.addExecutable("step4_if_fn_do",   "step4_if_fn_do.zig"),
-        b.addExecutable("step5_tco",        "step5_tco.zig"),
-        b.addExecutable("step6_file",       "step6_file.zig"),
-        b.addExecutable("step7_quote",      "step7_quote.zig"),
-        b.addExecutable("step8_macros",     "step8_macros.zig"),
-        b.addExecutable("step9_try",        "step9_try.zig"),
-        b.addExecutable("stepA_mal",        "stepA_mal.zig"),
-    };
+    //  Two options select the built step.
+
+    const name = b.option([]const u8, "name", "step name (without .zig)")
+                 orelse "stepA_mal";
+
+    const root_source_file = b.path(
+        b.option([]const u8, "root_source_file", "step name (with .zig)")
+        orelse "stepA_mal.zig");
+
+    const exe = b.addExecutable(.{
+        .name = name,
+        .root_source_file = root_source_file,
+        .target = b.standardTargetOptions(.{}),
+        .optimize = b.standardOptimizeOption(.{}),
+    });
 
-    for(exes) |exe| {
-        exe.setBuildMode(mode);
-        exe.linkSystemLibrary("c");
-        exe.linkSystemLibrary("pcre");
-        exe.linkSystemLibrary("readline");
-        const run_cmd = exe.run();
-        const step = b.step(exe.name, exe.name);
-        step.dependOn(&run_cmd.step);
-        b.default_step.dependOn(&exe.step);
-        b.installArtifact(exe);
-    }
+    exe.linkSystemLibrary("c");
+    exe.linkSystemLibrary("pcre");
+    exe.linkSystemLibrary("readline");
+    b.default_step.dependOn(&exe.step);
+    b.installArtifact(exe);
 }