literals.md
In treesitter.r: 'R' Grammar for 'Tree-Sitter'

identifiers

Code
  node_children_print(node)
Output
  S-Expression
  (identifier [(1, 0), (1, 3)])

  Text
  foo

  S-Expression
  (identifier [(2, 0), (2, 4)])

  Text
  foo2

  S-Expression
  (identifier [(3, 0), (3, 7)])

  Text
  foo.bar

  S-Expression
  (identifier [(4, 0), (4, 8)])

  Text
  .foo.bar

  S-Expression
  (identifier [(5, 0), (5, 15)])

  Text
  .__NAMESPACE__.

  S-Expression
  (identifier [(6, 0), (6, 7)])

  Text
  foo_bar

  S-Expression
  (identifier [(7, 0), (7, 6)])

  Text
  `_foo`

  S-Expression
  (identifier [(8, 0), (8, 13)])

  Text
  `a "literal"`

  S-Expression
  (identifier [(9, 0), (10, 15)])

  Text
  `another
  literal \` foo`

  S-Expression
  (identifier [(11, 0), (12, 1)])

  Text
  `backslash followed by newline \
  `

  S-Expression
  (identifier [(13, 0), (13, 4)])

  Text
  `\``

  S-Expression
  (comment [(14, 0), (14, 18)])

  Text
  # Pipe placeholder

  S-Expression
  (identifier [(15, 0), (15, 1)])

  Text
  _

  S-Expression
  (comment [(16, 0), (16, 73)])

  Text
  # Recognized as a single `_foo` identifier, even if invalid R code (#71).

  S-Expression
  (identifier [(17, 0), (17, 4)])

  Text
  _foo

  S-Expression
  (identifier [(18, 0), (18, 5)])

  Text
  __foo

  S-Expression
  (identifier [(19, 0), (19, 5)])

  Text
  _foo_

comments

Code
  node_children_print(node)
Output
  S-Expression
  (comment [(1, 0), (1, 12)])

  Text
  # a comment'

  S-Expression
  (string [(3, 0), (3, 17)]
    open: "'" [(3, 0), (3, 1)]
    content: (string_content [(3, 1), (3, 16)])
    close: "'" [(3, 16), (3, 17)]
  )

  Text
  '# not a comment'

  S-Expression
  (string [(6, 0), (7, 22)]
    open: "'" [(6, 0), (6, 1)]
    content: (string_content [(6, 1), (7, 21)])
    close: "'" [(7, 21), (7, 22)]
  )

  Text
  '
  # still not a comment'

constants

Code
  node_children_print(node)
Output
  S-Expression
  (true [(1, 0), (1, 4)])

  Text
  TRUE

  S-Expression
  (false [(2, 0), (2, 5)])

  Text
  FALSE

  S-Expression
  (null [(3, 0), (3, 4)])

  Text
  NULL

  S-Expression
  (inf [(4, 0), (4, 3)])

  Text
  Inf

  S-Expression
  (nan [(5, 0), (5, 3)])

  Text
  NaN

  S-Expression
  (na [(6, 0), (6, 2)]
    "NA" [(6, 0), (6, 2)]
  )

  Text
  NA

  S-Expression
  (na [(7, 0), (7, 8)]
    "NA_real_" [(7, 0), (7, 8)]
  )

  Text
  NA_real_

  S-Expression
  (na [(8, 0), (8, 13)]
    "NA_character_" [(8, 0), (8, 13)]
  )

  Text
  NA_character_

  S-Expression
  (na [(9, 0), (9, 11)]
    "NA_complex_" [(9, 0), (9, 11)]
  )

  Text
  NA_complex_

integers

Code
  node_children_print(node)
Output
  S-Expression
  (integer [(1, 0), (1, 6)]
    "L" [(1, 5), (1, 6)]
  )

  Text
  12332L

  S-Expression
  (integer [(2, 0), (2, 2)]
    "L" [(2, 1), (2, 2)]
  )

  Text
  0L

  S-Expression
  (integer [(3, 0), (3, 3)]
    "L" [(3, 2), (3, 3)]
  )

  Text
  12L

floats

Code
  node_children_print(node)
Output
  S-Expression
  (float [(1, 0), (1, 3)])

  Text
  .66

  S-Expression
  (float [(2, 0), (2, 3)])

  Text
  .11

  S-Expression
  (float [(3, 0), (3, 8)])

  Text
  123.4123

  S-Expression
  (float [(4, 0), (4, 5)])

  Text
  .1234

  S-Expression
  (binary_operator [(5, 0), (5, 9)]
    lhs: (identifier [(5, 0), (5, 1)])
    operator: "<-" [(5, 2), (5, 4)]
    rhs: (unary_operator [(5, 5), (5, 9)]
      operator: "-" [(5, 5), (5, 6)]
      rhs: (float [(5, 6), (5, 9)])
    )
  )

  Text
  x <- -.66

hexadecimal

Code
  node_children_print(node)
Output
  S-Expression
  (comment [(1, 0), (1, 12)])

  Text
  # `x` vs `X`

  S-Expression
  (float [(2, 0), (2, 5)])

  Text
  0x123

  S-Expression
  (float [(3, 0), (3, 5)])

  Text
  0X123

  S-Expression
  (comment [(5, 0), (5, 21)])

  Text
  # Numbers and letters

  S-Expression
  (float [(6, 0), (6, 6)])

  Text
  0xDEAD

  S-Expression
  (float [(7, 0), (7, 6)])

  Text
  0XDEAD

  S-Expression
  (float [(8, 0), (8, 7)])

  Text
  0x1f2F3

  S-Expression
  (float [(9, 0), (9, 7)])

  Text
  0X1f2F3

  S-Expression
  (comment [(11, 0), (11, 12)])

  Text
  # `p` vs `P`

  S-Expression
  (float [(12, 0), (12, 5)])

  Text
  0x0p0

  S-Expression
  (float [(13, 0), (13, 5)])

  Text
  0x0P0

  S-Expression
  (float [(14, 0), (14, 7)])

  Text
  0x0p123

  S-Expression
  (float [(15, 0), (15, 7)])

  Text
  0x0P123

  S-Expression
  (comment [(17, 0), (17, 13)])

  Text
  # `+` and `-`

  S-Expression
  (float [(18, 0), (18, 6)])

  Text
  0x0p+0

  S-Expression
  (float [(19, 0), (19, 6)])

  Text
  0x0p-0

  S-Expression
  (float [(20, 0), (20, 8)])

  Text
  0x0p+123

  S-Expression
  (float [(21, 0), (21, 8)])

  Text
  0x0p-123

  S-Expression
  (comment [(23, 0), (23, 13)])

  Text
  # As integers

  S-Expression
  (integer [(24, 0), (24, 6)]
    "L" [(24, 5), (24, 6)]
  )

  Text
  0x123L

  S-Expression
  (integer [(25, 0), (25, 6)]
    "L" [(25, 5), (25, 6)]
  )

  Text
  0X123L

  S-Expression
  (integer [(26, 0), (26, 7)]
    "L" [(26, 6), (26, 7)]
  )

  Text
  0xDEADL

  S-Expression
  (integer [(27, 0), (27, 7)]
    "L" [(27, 6), (27, 7)]
  )

  Text
  0XDEADL

  S-Expression
  (integer [(28, 0), (28, 6)]
    "L" [(28, 5), (28, 6)]
  )

  Text
  0x0p0L

  S-Expression
  (integer [(29, 0), (29, 6)]
    "L" [(29, 5), (29, 6)]
  )

  Text
  0x0P0L

  S-Expression
  (integer [(30, 0), (30, 7)]
    "L" [(30, 6), (30, 7)]
  )

  Text
  0x0p+0L

  S-Expression
  (integer [(31, 0), (31, 7)]
    "L" [(31, 6), (31, 7)]
  )

  Text
  0x0p-0L

scientific notation floats

Code
  node_children_print(node)
Output
  S-Expression
  (float [(1, 0), (1, 5)])

  Text
  1e322

  S-Expression
  (float [(2, 0), (2, 4)])

  Text
  1e-3

  S-Expression
  (float [(3, 0), (3, 4)])

  Text
  1e+3

  S-Expression
  (float [(4, 0), (4, 6)])

  Text
  1.8e10

  S-Expression
  (float [(5, 0), (5, 5)])

  Text
  1.e10

  S-Expression
  (float [(6, 0), (6, 4)])

  Text
  1e10