* Improve features for NER

spacy/syntax/_parse_features.pxd

@@ -187,6 +187,28 @@ cpdef enum:
     P2_suffix
     P2_shape
    
+    E0w
+    E0W
+    E0p
+    E0c
+    E0c4
+    E0c6
+    E0L
+    E0_prefix
+    E0_suffix
+    E0_shape
+   
+    E1w
+    E1W
+    E1p
+    E1c
+    E1c4
+    E1c6
+    E1L
+    E1_prefix
+    E1_suffix
+    E1_shape
+   
     # Misc features at the end
     dist
     N0lv

spacy/syntax/_parse_features.pyx

@@ -13,6 +13,7 @@ from ..tokens cimport TokenC
 from ._state cimport State
 from ._state cimport get_s2, get_s1, get_s0, get_n0, get_n1, get_n2
 from ._state cimport get_p2, get_p1
+from ._state cimport get_e0, get_e1
 from ._state cimport has_head, get_left, get_right
 from ._state cimport count_left_kids, count_right_kids
 
@@ -69,6 +70,8 @@ cdef int fill_context(atom_t* context, State* state) except -1:
     fill_token(&context[P1w], get_p1(state))
     fill_token(&context[P2w], get_p2(state))
 
+    fill_token(&context[E0w], get_e0(state))
+    fill_token(&context[E1w], get_e1(state))
     if state.stack_len >= 1:
         context[dist] = state.stack[0] - state.i
     else:
@@ -135,6 +138,32 @@ ner = (
 
     (P1c, N0c),
     (N0c, N1c),
+
+    (E0w,),
+    (E0c,),
+    (E0p,),
+
+    (E0w, N0w),
+    (E0c, N0w),
+    (E0p, N0w),
+
+    (E0p, P1p, N0p),
+    (E0c, P1c, N0c),
+
+    (E0w, P1c),
+    (E0p, P1p),
+    (E0c, P1c),
+    (E0p, E1p),
+    (E0c, P1p),
+
+    (E1w,),
+    (E1c,),
+    (E1p,),
+
+    (E0w, E1w),
+    (E0w, E1p,),
+    (E0p, E1w,),
+    (E0p, E1w),
 )
 
 

spacy/syntax/_state.pxd

@@ -54,6 +54,19 @@ cdef inline TokenC* get_p2(const State* s) nogil:
         return &s.sent[s.i-2]
 
 
+cdef inline TokenC* get_e0(const State* s) nogil:
+    if s.ent.end != 0:
+        return NULL
+    else:
+        return &s.sent[s.ent.start]
+
+
+cdef inline TokenC* get_e1(const State* s) nogil:
+    if s.ent.end != 0 or s.ent.start >= (s.i + 1):
+        return NULL
+    else:
+        return &s.sent[s.ent.start + 1]
+
 
 cdef inline TokenC* get_n2(const State* s) nogil:
     if (s.i + 2) >= s.sent_len: