1 files changed, 66 insertions, 0 deletions
diff --git a/src/parse.c b/src/parse.c
new file mode 100644
index 0000000..f2f89cd
--- /dev/null
+++ b/src/parse.c
@@ -0,0 +1,66 @@
+// Copyright (c) 2024, Marvin Borner <dev@marvinborner.de>
+// SPDX-License-Identifier: MIT
+
+#include <parse.h>
+#include <log.h>
+#include <term.h>
+
+Term *parse_blc_fp(FILE *fp)
+{
+	Term *res = 0;
+
+	char a = getc(fp);
+
+	if (a == '0') {
+		char b = getc(fp);
+		if (b == '0') {
+			res = term_new(ABS);
+			res->u.abs.body = parse_blc_fp(fp);
+		}
+		if (b == '1') {
+			res = term_new(APP);
+			res->u.app.lhs = parse_blc_fp(fp);
+			res->u.app.rhs = parse_blc_fp(fp);
+		}
+	}
+
+	if (a == '1') {
+		res = term_new(IDX);
+		res->u.index = 0;
+		while (getc(fp) == '1')
+			res->u.index++;
+	}
+
+	if (!res)
+		fatal("invalid parsing state!\n");
+
+	return res;
+}
+
+Term *parse_blc(const char **term)
+{
+	Term *res = 0;
+	if (!**term) {
+		fatal("invalid parsing state!\n");
+	} else if (**term == '0' && *(*term + 1) == '0') {
+		(*term) += 2;
+		res = term_new(ABS);
+		res->u.abs.body = parse_blc(term);
+	} else if (**term == '0' && *(*term + 1) == '1') {
+		(*term) += 2;
+		res = term_new(APP);
+		res->u.app.lhs = parse_blc(term);
+		res->u.app.rhs = parse_blc(term);
+	} else if (**term == '1') {
+		const char *cur = *term;
+		while (**term == '1')
+			(*term)++;
+		res = term_new(IDX);
+		res->u.index = *term - cur - 1;
+		(*term)++;
+	} else {
+		(*term)++;
+		res = parse_blc(term);
+	}
+	return res;
+}