a more general way of including packages which enables providing package options

aastex62/aastex62_template.tex

@@ -13,11 +13,17 @@ $if(bibstyle)$
 $endif$
 
 $if(texpackages)$
-\usepackage{
 $for(texpackages)$
-$texpackages$,
+\usepackage
+$if(opts)$
+[
+$for(opts)$
+$opts$,
+$endfor$
+]
+$endif$
+{$texpackages.name$}
 $endfor$
-}
 $endif$
 
 $if(preambleinput)$

aastex62/demo.md

@@ -1,7 +1,11 @@
 ---
 aastexopts: [singlecolumn]
 preambleinput: ["macros.tex"]
-texpackages: [xspace, amsmath]
+texpackages:
+- name: xspace
+#  opts: 
+- name: amsmath
+#  opts: 
 bibstyle: aasjournal
 received: "January 1, 2018"
 #revised: "January 7, 2018"