StringContains

Whether one string occurs inside another.

Declaration

Syntax

StringContains(expr substr, expr str, ttype type, expr? value)

Arguments

Argument

Description

substr

the string looked for.

str

the string looked in.

type

the logical type of the result.

value

the compile time value of the expression, when the frontend could fold it; nil otherwise.

Return values

The value of the expression.

Description

The result is logical. Fortran’s index returns a position instead and is an intrinsic call; StringContains is the membership test LPython’s in needs.

Examples

(StringContains
  :substr (StringConstant
    :s "ell"
    :type (String
      :kind 1
      :len (IntegerConstant
        :n 3
        :type (Integer
          :kind 4
        )
        :intboz_type :Decimal
      )
      :len_kind :ExpressionLength
      :physical_type :DescriptorString
    )
  )
  :str (Var
    :v (SymbolRef 1 "s")
  )
  :type (Logical
    :kind 4
  )
  :value nil
)

It comes from this complete ASR text document:

(TranslationUnit
  :symtab (SymbolTable
    :id 0
    :symbols {
      "main" (Program
        :symtab (SymbolTable
          :id 1
          :symbols {
            "b" (Variable
              :parent_symtab 1
              :name "b"
              :dependencies []
              :intent :Local
              :symbolic_value nil
              :value nil
              :storage :Default
              :type (Logical
                :kind 4
              )
              :type_declaration nil
              :abi :Source
              :access :Public
              :presence :Required
              :value_attr false
              :target_attr false
              :contiguous_attr false
              :bindc_name nil
              :is_volatile false
              :is_protected false
              :pass_attr :NotMethod
              :self_argument nil
              :codims []
            )
            "c" (Variable
              :parent_symtab 1
              :name "c"
              :dependencies []
              :intent :Local
              :symbolic_value nil
              :value nil
              :storage :Default
              :type (String
                :kind 1
                :len (IntegerConstant
                  :n 1
                  :type (Integer
                    :kind 4
                  )
                  :intboz_type :Decimal
                )
                :len_kind :ExpressionLength
                :physical_type :DescriptorString
              )
              :type_declaration nil
              :abi :Source
              :access :Public
              :presence :Required
              :value_attr false
              :target_attr false
              :contiguous_attr false
              :bindc_name nil
              :is_volatile false
              :is_protected false
              :pass_attr :NotMethod
              :self_argument nil
              :codims []
            )
            "n" (Variable
              :parent_symtab 1
              :name "n"
              :dependencies []
              :intent :Local
              :symbolic_value nil
              :value nil
              :storage :Default
              :type (Integer
                :kind 4
              )
              :type_declaration nil
              :abi :Source
              :access :Public
              :presence :Required
              :value_attr false
              :target_attr false
              :contiguous_attr false
              :bindc_name nil
              :is_volatile false
              :is_protected false
              :pass_attr :NotMethod
              :self_argument nil
              :codims []
            )
            "s" (Variable
              :parent_symtab 1
              :name "s"
              :dependencies []
              :intent :Local
              :symbolic_value nil
              :value nil
              :storage :Default
              :type (String
                :kind 1
                :len (IntegerConstant
                  :n 5
                  :type (Integer
                    :kind 4
                  )
                  :intboz_type :Decimal
                )
                :len_kind :ExpressionLength
                :physical_type :DescriptorString
              )
              :type_declaration nil
              :abi :Source
              :access :Public
              :presence :Required
              :value_attr false
              :target_attr false
              :contiguous_attr false
              :bindc_name nil
              :is_volatile false
              :is_protected false
              :pass_attr :NotMethod
              :self_argument nil
              :codims []
            )
            "t" (Variable
              :parent_symtab 1
              :name "t"
              :dependencies []
              :intent :Local
              :symbolic_value nil
              :value nil
              :storage :Default
              :type (Allocatable
                :type (String
                  :kind 1
                  :len nil
                  :len_kind :DeferredLength
                  :physical_type :DescriptorString
                )
              )
              :type_declaration nil
              :abi :Source
              :access :Public
              :presence :Required
              :value_attr false
              :target_attr false
              :contiguous_attr false
              :bindc_name nil
              :is_volatile false
              :is_protected false
              :pass_attr :NotMethod
              :self_argument nil
              :codims []
            )
          }
        )
        :name "main"
        :dependencies []
        :body [
          (Assignment
            :target (Var
              :v (SymbolRef 1 "s")
            )
            :value (StringConstant
              :s "hello"
              :type (String
                :kind 1
                :len (IntegerConstant
                  :n 5
                  :type (Integer
                    :kind 4
                  )
                  :intboz_type :Decimal
                )
                :len_kind :ExpressionLength
                :physical_type :DescriptorString
              )
            )
            :overloaded nil
            :realloc_lhs false
            :move_allocation false
          )
          (Assignment
            :target (Var
              :v (SymbolRef 1 "t")
            )
            :value (StringConcat
              :left (Var
                :v (SymbolRef 1 "s")
              )
              :right (StringConstant
                :s "!"
                :type (String
                  :kind 1
                  :len (IntegerConstant
                    :n 1
                    :type (Integer
                      :kind 4
                    )
                    :intboz_type :Decimal
                  )
                  :len_kind :ExpressionLength
                  :physical_type :DescriptorString
                )
              )
              :type (String
                :kind 1
                :len nil
                :len_kind :DeferredLength
                :physical_type :DescriptorString
              )
              :value nil
            )
            :overloaded nil
            :realloc_lhs false
            :move_allocation false
          )
          (Assignment
            :target (Var
              :v (SymbolRef 1 "t")
            )
            :value (StringRepeat
              :left (Var
                :v (SymbolRef 1 "s")
              )
              :right (IntegerConstant
                :n 3
                :type (Integer
                  :kind 4
                )
                :intboz_type :Decimal
              )
              :type (String
                :kind 1
                :len nil
                :len_kind :DeferredLength
                :physical_type :DescriptorString
              )
              :value nil
            )
            :overloaded nil
            :realloc_lhs false
            :move_allocation false
          )
          (Assignment
            :target (Var
              :v (SymbolRef 1 "n")
            )
            :value (StringLen
              :arg (Var
                :v (SymbolRef 1 "s")
              )
              :type (Integer
                :kind 4
              )
              :value nil
            )
            :overloaded nil
            :realloc_lhs false
            :move_allocation false
          )
          (Assignment
            :target (Var
              :v (SymbolRef 1 "c")
            )
            :value (StringItem
              :arg (Var
                :v (SymbolRef 1 "s")
              )
              :idx (IntegerConstant
                :n 1
                :type (Integer
                  :kind 4
                )
                :intboz_type :Decimal
              )
              :type (String
                :kind 1
                :len (IntegerConstant
                  :n 1
                  :type (Integer
                    :kind 4
                  )
                  :intboz_type :Decimal
                )
                :len_kind :ExpressionLength
                :physical_type :DescriptorString
              )
              :value nil
            )
            :overloaded nil
            :realloc_lhs false
            :move_allocation false
          )
          (Assignment
            :target (Var
              :v (SymbolRef 1 "t")
            )
            :value (StringSection
              :arg (Var
                :v (SymbolRef 1 "s")
              )
              :start (IntegerConstant
                :n 2
                :type (Integer
                  :kind 4
                )
                :intboz_type :Decimal
              )
              :end (IntegerConstant
                :n 4
                :type (Integer
                  :kind 4
                )
                :intboz_type :Decimal
              )
              :step (IntegerConstant
                :n 1
                :type (Integer
                  :kind 4
                )
                :intboz_type :Decimal
              )
              :type (String
                :kind 1
                :len (IntegerConstant
                  :n 3
                  :type (Integer
                    :kind 4
                  )
                  :intboz_type :Decimal
                )
                :len_kind :ExpressionLength
                :physical_type :DescriptorString
              )
              :value nil
            )
            :overloaded nil
            :realloc_lhs false
            :move_allocation false
          )
          (Assignment
            :target (Var
              :v (SymbolRef 1 "b")
            )
            :value (StringCompare
              :left (Var
                :v (SymbolRef 1 "s")
              )
              :op :Eq
              :right (StringConstant
                :s "world"
                :type (String
                  :kind 1
                  :len (IntegerConstant
                    :n 5
                    :type (Integer
                      :kind 4
                    )
                    :intboz_type :Decimal
                  )
                  :len_kind :ExpressionLength
                  :physical_type :DescriptorString
                )
              )
              :type (Logical
                :kind 4
              )
              :value nil
            )
            :overloaded nil
            :realloc_lhs false
            :move_allocation false
          )
          (Assignment
            :target (Var
              :v (SymbolRef 1 "b")
            )
            :value (StringContains
              :substr (StringConstant
                :s "ell"
                :type (String
                  :kind 1
                  :len (IntegerConstant
                    :n 3
                    :type (Integer
                      :kind 4
                    )
                    :intboz_type :Decimal
                  )
                  :len_kind :ExpressionLength
                  :physical_type :DescriptorString
                )
              )
              :str (Var
                :v (SymbolRef 1 "s")
              )
              :type (Logical
                :kind 4
              )
              :value nil
            )
            :overloaded nil
            :realloc_lhs false
            :move_allocation false
          )
          (Assignment
            :target (Var
              :v (SymbolRef 1 "n")
            )
            :value (StringOrd
              :arg (Var
                :v (SymbolRef 1 "c")
              )
              :type (Integer
                :kind 4
              )
              :value nil
            )
            :overloaded nil
            :realloc_lhs false
            :move_allocation false
          )
          (Assignment
            :target (Var
              :v (SymbolRef 1 "c")
            )
            :value (StringChr
              :arg (IntegerConstant
                :n 65
                :type (Integer
                  :kind 4
                )
                :intboz_type :Decimal
              )
              :type (String
                :kind 1
                :len (IntegerConstant
                  :n 1
                  :type (Integer
                    :kind 4
                  )
                  :intboz_type :Decimal
                )
                :len_kind :ExpressionLength
                :physical_type :DescriptorString
              )
              :value nil
            )
            :overloaded nil
            :realloc_lhs false
            :move_allocation false
          )
          (Assignment
            :target (Var
              :v (SymbolRef 1 "n")
            )
            :value (Ichar
              :arg (Var
                :v (SymbolRef 1 "c")
              )
              :type (Integer
                :kind 4
              )
              :value nil
            )
            :overloaded nil
            :realloc_lhs false
            :move_allocation false
          )
          (Assignment
            :target (Var
              :v (SymbolRef 1 "n")
            )
            :value (Iachar
              :arg (Var
                :v (SymbolRef 1 "c")
              )
              :type (Integer
                :kind 4
              )
              :value nil
            )
            :overloaded nil
            :realloc_lhs false
            :move_allocation false
          )
        ]
      )
    }
  )
  :items []
)

See Also

StringCompare, StringItem, IntrinsicElementalFunction