1 files changed, 21 insertions, 0 deletions
diff --git a/bash.md b/bash.md
index d150702..41e8f05 100644
--- a/bash.md
+++ b/bash.md
@@ -29,6 +29,27 @@ Loop over integers
 ## Conditionals
 
 * `-z`: is empty string
+* `-n`: non-empty string
 * `-f`: is regular file
 * `$A == $B`: string equality, accepts globs
 * `$A != $B`: string inequality
+
+## Heredocs
+
+    cat << EOF > file
+    bla bla
+    EOF
+
+Ignoring the initial indent:
+
+    ...
+        cat <<- EOF > file
+        bla bla
+        EOF
+    ...
+
+Don't interpolate variables:
+
+    cat << 'EOF' > file
+    bla bla
+    EOF