Move anno-edit type hints entirely into translation JSON (#451)

This also adds dynamism so that the translation strings cannot be
requested before they are available.

frontend/src/i18n/en/translation.json

@@ -30,10 +30,10 @@
   "permitted_types_before_list": "This property permits",
   "current_type": "Current type:",
   "typeHints": {
-    "integer": "",
-    "base64Binary": "",
-    "gYear": "",
-    "string": ""
+    "integer": "Include extra leading zeros to force interpretation as an integer type.",
+    "base64Binary": "Include internal whitespace to force interpretation as base 64 binary data.",
+    "gYear": "Include time zone information (such as a final “Z”) to force interpretation as a Gregorian year.",
+    "string": "Start with a space to force interpretation as text or a derived string type."
   },
   "all_types_permitted": "This property permits any simple type.",
   "no_type_matched": "This value does not match the permitted type(s).",

frontend/src/i18n/fr/translation.json

@@ -30,10 +30,10 @@
   "permitted_types_before_list": "This property permits",
   "current_type": "Current type:",
   "typeHints": {
-    "integer": "",
-    "base64Binary": "",
-    "gYear": "",
-    "string": ""
+    "integer": "Include extra leading zeros to force interpretation as an integer type.",
+    "base64Binary": "Include internal whitespace to force interpretation as base 64 binary data.",
+    "gYear": "Include time zone information (such as a final “Z”) to force interpretation as a Gregorian year.",
+    "string": "Start with a space to force interpretation as text or a derived string type."
   },
   "all_types_permitted": "This property permits any simple type.",
   "no_type_matched": "This value does not match the permitted type(s).",

frontend/src/item-edit/detected-type-help-view.ts

@@ -1,4 +1,4 @@
-import { map, extend, propertyOf } from 'lodash';
+import { map, extend, fromPairs } from 'lodash';
 import * as i18next from 'i18next';
 
 import { CompositeView } from '../core/view';
@@ -8,26 +8,14 @@ import { xsd } from '../common-rdf/ns';
 import ScopedIriLink from './scoped-iri-href-view';
 import template from './detected-type-help-template';
 
-const disambiguationHints = {
-    [xsd.integer]: i18next.t('typeHints.integer',
-        'Include extra leading zeros to force interpretation ' +
-        'as an integer type.'
-    ),
-    [xsd.base64Binary]: i18next.t('typeHints.base64Binary',
-        'Include internal whitespace to force interpretation ' +
-        'as base 64 binary data.'
-    ),
-    [xsd.gYear]: i18next.t('typeHints.gYear',
-        'Include time zone information (such as a final "Z") to force ' +
-        'interpretation as a Gregorian year.'
-    ),
-    [xsd.string]: i18next.t('typeHints.string',
-        'Start with a space to force interpretation as text or ' +
-        'a derived string type.'
-    ),
-};
-
-const getHint = propertyOf(disambiguationHints);
+// i18next.t('typeHints.integer')
+// i18next.t('typeHints.base64Binary')
+// i18next.t('typeHints.gYear')
+// i18next.t('typeHints.string')
+const typesWithHints = ['integer', 'base64Binary', 'gYear', 'string'];
+const typeAsPair = name => [xsd[name], `typeHints.${name}`];
+const disambiguationHints = fromPairs(map(typesWithHints, typeAsPair));
+const getHint = type => i18next.t(disambiguationHints[type]);
 
 /**
  * This is one of the p.help views used in LinkedItemEditor, to give the user