dc

commit 9d3fefb466d402687dd335e210db9199908aa635
parent 59378f18dba3c1ff12f70650be06c439bacef385
Author: Byron Torres <b@torresjrjr.com>
Date:   Mon, 22 Nov 2021 09:31:44 +0000

write initial interface, add Makefile

Diffstat:
A
.gitignore
 | 
2
++
A
Makefile
 | 
13
+++++++++++++
M
README.md
 | 
8
++++++++
A
dc.ha
 | 
49
+++++++++++++++++++++++++++++++++++++++++++++++++

4 files changed, 72 insertions(+), 0 deletions(-)
diff --git a/.gitignore b/.gitignore
@@ -0,0 +1,2 @@
+dc
+tmp/
diff --git a/Makefile b/Makefile
@@ -0,0 +1,13 @@
+.POSIX:
+HARE=hare
+HAREFLAGS=
+
+all: dc
+
+dc: dc.ha
+	$(HARE) build $(HAREFLAGS) -o $@ $<
+
+clean:
+	rm -f dc
+
+.PHONY: all clean
diff --git a/README.md b/README.md
@@ -1 +1,9 @@
 # dc
+
+An implementation of dc,
+the desk calculator,
+wriiten in Hare.
+
+(pre-alpha)
+
+Send patches to <b@torresjrjr.com>.
diff --git a/dc.ha b/dc.ha
@@ -0,0 +1,49 @@
+use bufio;
+use encoding::utf8;
+use fmt;
+use getopt;
+use io;
+use os;
+
+export fn main() void = {
+	const help: [_]getopt::help = [
+		"desk calculator",
+		"[file]",
+	];
+	const cmd = getopt::parse(os::args, help...);
+	defer getopt::finish(&cmd);
+
+	if (len(cmd.args) > 1) {
+		usage_exit(help);
+	};
+
+	let filename: (str | void) = if (len(cmd.args) == 1)
+		switch (cmd.args[0]) {
+		case "-" =>
+			fmt::fatal("dc: invalid filename '-'");
+		case "" =>
+			fmt::fatal("dc: invalid filename ''");
+		case =>
+			yield cmd.args[0];
+		}
+	else
+		void;
+
+	for (true) {
+		const r = match (bufio::scanrune(os::stdin)) {
+		case utf8::invalid =>
+			fmt::fatal("dc: invalid utf8 input");
+		case io::error =>
+			fmt::fatal("dc: IO error");
+		case io::EOF =>
+			break;
+		case r: rune =>
+			yield r;
+		};
+	};
+};
+
+@noreturn fn usage_exit(help: []getopt::help) void = {
+	getopt::printusage(os::stderr, os::args[0], help);
+	os::exit(1);
+};