remove strong dep with sf

Author: eblondel

DESCRIPTION

@@ -10,8 +10,8 @@ Description: Provides facilities to handle reading and writing of geographic met
  and encoded using the ISO 19139 (XML) standard. It includes also a facility to check
  the validity of ISO 19139 XML encoded metadata.
 Depends: R (>= 3.3.0)
-Imports: R6, XML, sf
-Suggests: testthat, roxygen2
+Imports: R6, XML
+Suggests: sf, testthat, roxygen2
 License: MIT + file LICENSE
 URL: https://github.com/eblondel/geometa/wiki
 BugReports: https://github.com/eblondel/geometa/issues

NAMESPACE

@@ -211,6 +211,5 @@ export(setISOCodelists)
 export(setISOMetadataNamespaces)
 export(setISOMetadataSchemas)
 import(XML)
-import(sf)
 importFrom(R6,R6Class)
 importFrom(utils,packageDescription)

R/GMLAbstractGeometry.R

@@ -29,6 +29,15 @@ GMLAbstractGeometry <- R6Class("GMLAbstractGeometry",
   private = list(
     xmlElement = "AbstractGeometry",
     xmlNamespacePrefix = "GML"
+  ),
+  public = list(
+    initialize = function(xml = NULL, element = NULL, attrs = list(), defaults = list(), wrap = TRUE){
+      if(is.null(element)) element <- private$xmlElement
+      super$initialize(xml, element = element, attrs = attrs, defaults = defaults, wrap = wrap)
+      if(!require("sf")){
+        stop("Creating GML geometry objects require 'sf' package")
+      }
+    }
   )
 )
 

R/ISOAbstractObject.R

@@ -4,7 +4,6 @@
 #' @importFrom utils packageDescription
 #' @importFrom R6 R6Class
 #' @import XML
-#' @import sf
 #' @export
 #' @keywords ISO metadata element
 #' @return Object of \code{\link{R6Class}} for modelling an ISO Metadata Element