hare

commit 2ec551087972ddb3535b0147de2c9c4b0620ee73
parent aef0a97bedd46608db499196f239c1a529801432
Author: Drew DeVault <sir@cmpwn.com>
Date:   Sat,  6 Mar 2021 16:40:46 -0500

os: add tryenv function

Diffstat:
M
os/+linux/environ.ha
 | 
7
+++++++

1 file changed, 7 insertions(+), 0 deletions(-)
diff --git a/os/+linux/environ.ha b/os/+linux/environ.ha
@@ -48,6 +48,13 @@ export fn getenv(name: const str) (str | void) = {
 	};
 };
 
+// Looks up an environment variable and returns its value, or a default value if
+// unset.
+export fn tryenv(name: const str, default: str) str = match (getenv(name)) {
+	s: str => s,
+	void => default,
+};
+
 let envp: []str = [];
 
 // Returns a slice of the environment strings in the form KEY=VALUE.