Class: TreeSitter::TreeCursor

Inherits:
Object
  • Object
show all
Defined in:
ext/tree_sitter/tree_cursor.c

Instance Method Summary collapse

Constructor Details

#initialize(node) ⇒ TreeCursor

Create a new tree cursor starting from the given node.

A tree cursor allows you to walk a syntax tree more efficiently than is possible using the Node functions. It is a mutable object that is always on a certain syntax node, and can be moved imperatively to different nodes.



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# File 'ext/tree_sitter/tree_cursor.c', line 206

static VALUE tree_cursor_initialize(VALUE self, VALUE node) {
  TSNode n = value_to_node(node);
  tree_cursor_t *ptr = unwrap(self);
  ptr->data = ts_tree_cursor_new(n);
  return self;
}

Instance Method Details

#copy ⇒ Object

Class methods

#current_depth ⇒ Integer

Get the depth of the cursor’s current node relative to the original node that the cursor was constructed with.

Returns:

  • (Integer) 


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# File 'ext/tree_sitter/tree_cursor.c', line 38

static VALUE tree_cursor_current_depth(VALUE self) {
  return UINT2NUM(ts_tree_cursor_current_depth(&SELF));
}

#current_descendant_index ⇒ Integer

Get the index of the cursor’s current node out of all of the descendants of the original node that the cursor was constructed with.

Returns:

  • (Integer) 


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# File 'ext/tree_sitter/tree_cursor.c', line 48

static VALUE tree_cursor_current_descendant_index(VALUE self) {
  return UINT2NUM(ts_tree_cursor_current_descendant_index(&SELF));
}

#current_field_id ⇒ Integer

Get the field id of the tree cursor’s current node.

This returns zero if the current node doesn’t have a field.

Returns:

  • (Integer)

See Also:



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# File 'ext/tree_sitter/tree_cursor.c', line 62

static VALUE tree_cursor_current_field_id(VALUE self) {
  return UINT2NUM(ts_tree_cursor_current_field_id(&SELF));
}

#current_field_name ⇒ String

Get the field name of the tree cursor’s current node.

This returns nil if the current node doesn’t have a field.

Returns:

  • (String)

See Also:



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# File 'ext/tree_sitter/tree_cursor.c', line 75

static VALUE tree_cursor_current_field_name(VALUE self) {
  return safe_str(ts_tree_cursor_current_field_name(&SELF));
}

#current_node ⇒ Node

Get the tree cursor’s current node.

Returns:



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# File 'ext/tree_sitter/tree_cursor.c', line 84

static VALUE tree_cursor_current_node(VALUE self) {
  TSNode node = ts_tree_cursor_current_node(&SELF);
  return new_node(&node);
}

#goto_descendant(descendant_idx) ⇒ nil

Move the cursor to the node that is the nth descendant of the original node that the cursor was constructed with, where zero represents the original node itself.

Returns:

  • (nil) 


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# File 'ext/tree_sitter/tree_cursor.c', line 96

static VALUE tree_cursor_goto_descendant(VALUE self, VALUE descendant_idx) {
  uint32_t idx = NUM2UINT(descendant_idx);
  ts_tree_cursor_goto_descendant(&SELF, idx);
  return Qnil;
}

#goto_first_child ⇒ Boolean

Move the cursor to the first child of its current node.

This returns true if the cursor successfully moved, and returns false if there were no children.

Returns:

  • (Boolean) 


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# File 'ext/tree_sitter/tree_cursor.c', line 110

static VALUE tree_cursor_goto_first_child(VALUE self) {
  return ts_tree_cursor_goto_first_child(&SELF) ? Qtrue : Qfalse;
}

#goto_first_child_for_byte(byte) ⇒ Integer

Move the cursor to the first child of its current node that extends beyond the given byte offset.

This returns the index of the child node if one was found, and returns -1 if no such child was found.

Returns:

  • (Integer) 


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# File 'ext/tree_sitter/tree_cursor.c', line 123

static VALUE tree_cursor_goto_first_child_for_byte(VALUE self, VALUE byte) {
  return LL2NUM(
      ts_tree_cursor_goto_first_child_for_byte(&SELF, NUM2UINT(byte)));
}

#goto_first_child_for_point(point) ⇒ Integer

Move the cursor to the first child of its current node that extends beyond the given or point.

This returns the index of the child node if one was found, and returns -1 if no such child was found.

Returns:

  • (Integer) 


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# File 'ext/tree_sitter/tree_cursor.c', line 137

static VALUE tree_cursor_goto_first_child_for_point(VALUE self, VALUE point) {
  return LL2NUM(
      ts_tree_cursor_goto_first_child_for_point(&SELF, value_to_point(point)));
}

#goto_last_child ⇒ Object

Move the cursor to the last child of its current node.

This returns true if the cursor successfully moved, and returns false if there were no children.

Note that this function may be slower than #goto_first_child because it needs to iterate through all the children to compute the child’s position.



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# File 'ext/tree_sitter/tree_cursor.c', line 152

static VALUE tree_cursor_goto_last_child(VALUE self) {
  return ts_tree_cursor_goto_last_child(&SELF) ? Qtrue : Qfalse;
}

#goto_next_sibling ⇒ Object

Move the cursor to the next sibling of its current node.

This returns true if the cursor successfully moved, and returns false if there was no next sibling node.

Returns:

  • Boolean



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# File 'ext/tree_sitter/tree_cursor.c', line 164

static VALUE tree_cursor_goto_next_sibling(VALUE self) {
  return ts_tree_cursor_goto_next_sibling(&SELF) ? Qtrue : Qfalse;
}

#goto_parent ⇒ Boolean

Move the cursor to the parent of its current node.

This returns true if the cursor successfully moved, and returns false if there was no parent node (the cursor was already on the root node).

Returns:

  • (Boolean) 


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# File 'ext/tree_sitter/tree_cursor.c', line 176

static VALUE tree_cursor_goto_parent(VALUE self) {
  return ts_tree_cursor_goto_parent(&SELF) ? Qtrue : Qfalse;
}

#goto_previous_sibling ⇒ Boolean

Move the cursor to the previous sibling of its current node.

This returns true if the cursor successfully moved, and returns false if there was no previous sibling node.

Note, that this function may be slower than #goto_next_sibling due to how node positions are stored. In the worst case, this will need to iterate through all the children upto the previous sibling node to recalculate its position.

Returns:

  • (Boolean) 


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# File 'ext/tree_sitter/tree_cursor.c', line 193

static VALUE tree_cursor_goto_previous_sibling(VALUE self) {
  return ts_tree_cursor_goto_previous_sibling(&SELF) ? Qtrue : Qfalse;
}

#reset(node) ⇒ nil

Re-initialize a tree cursor to start at a different node.

Returns:

  • (nil) 


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# File 'ext/tree_sitter/tree_cursor.c', line 218

static VALUE tree_cursor_reset(VALUE self, VALUE node) {
  ts_tree_cursor_reset(&SELF, value_to_node(node));
  return Qnil;
}

#reset_to(src) ⇒ nil

Re-initialize a tree cursor to the same position as another cursor.

Unlike #reset, this will not lose parent information and allows reusing already created cursors.

Returns:

  • (nil) 


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# File 'ext/tree_sitter/tree_cursor.c', line 231

VALUE tree_cursor_reset_to(VALUE self, VALUE src) {
  ts_tree_cursor_reset_to(&SELF, &unwrap(src)->data);
  return Qnil;
}