entity - MrKaszeba19/PapajLang GitHub Wiki

Entity – a single computable element in PapajScript.

The first entities, Number and String, were introduced on April 26, 2018 with the release of the RPN 0.4.0.

Current usable entity types:

• Number, e.g. 5, 2, -10, 20.5 etc.
  More explanation here.
• String, e.g. "Hello world!", "Shalom!", "h" etc.
  More explanation here.
  See the functions for strings in the String package.
• Boolean, e.g. TRUE, FALSE
  See the logical functions here.
• Null, e.g. NULL
• Function, e.g. fun{ -1 * } etc.
  More explanation here.
• Exception, e.g. EXC (as of now just basic ones, to be improved)
• Array, e.g. [], [ 2 1 3 7 ], [ 10 times rand ]
  More explanation here.
  See the functions for arrays in the Array package.
• LogicalExpression, e.g. ( x 0 > )
  More explanation here.
• DateTime, e.g. "2005-04-02 21:37:00" Date.toDateTime More explanation here.
  See the functions for arrays in the Date package.

Quasi-types:

• InstructionBlock, e.g. { x 2 ^ 2 / }

Planned for the future

• Object
• File
• Dataframe

Current unusable data types:

• Unknown

Removed/replaced types:

• Expression, e.g. ( x 0 > ) – replaced by LogicalExpression in September 2020

Syntax: X command

Programme Operand	Purpose
toString	convert to a string
toNumber	convert to a number
toBoolean	convert to a logical value true or false
toArray	build an array from N elements of the stack
toException	build an exception (if X is a string, then it creates an unraised exception with this string message)
Date.toDateTime	builds a datetime either from a string or a real number (assuming it represents Unix epoch time)
raiseException	same as above, but it raises exception too

Syntax: X command

• type returns a string containing entity type, e.g. "String"
• isNumber, isBoolean, isString, isArray, isNull, isException, isLogicalExpression, isFunction, isDateTime – return TRUE or FALSE relatively if an entity is of a type mentioned in the function