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https://github.com/CHOMPStation2/CHOMPStation2.git
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25c1ec5287
Co-authored-by: Selis <12716288+ItsSelis@users.noreply.github.com> Co-authored-by: Kashargul <144968721+Kashargul@users.noreply.github.com>
128 lines
3.2 KiB
Plaintext
128 lines
3.2 KiB
Plaintext
/*
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File: AST Nodes
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An abstract syntax tree (AST) is a representation of source code in a computer-friendly format. It is composed of nodes,
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each of which represents a certain part of the source code. For example, an <IfStatement> node represents an if statement in the
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script's source code. Because it is a representation of the source code in memory, it is independent of any specific scripting language.
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This allows a script in any language for which a parser exists to be run by the interpreter.
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The AST is produced by an <n_Parser> object. It consists of a <GlobalBlock> with an arbitrary amount of statements. These statements are
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run in order by an <n_Interpreter> object. A statement may in turn run another block (such as an if statement might if its condition is
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met).
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Articles:
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- <http://en.wikipedia.org/wiki/Abstract_syntax_tree>
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*/
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/*
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Constants: Operator Precedence
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OOP_OR - Logical or
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OOP_AND - Logical and
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OOP_BIT - Bitwise operations
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OOP_EQUAL - Equality checks
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OOP_COMPARE - Greater than, less then, etc
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OOP_ADD - Addition and subtraction
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OOP_MULTIPLY - Multiplication and division
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OOP_POW - Exponents
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OOP_UNARY - Unary Operators
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OOP_GROUP - Parentheses
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*/
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var/const/OOP_OR = 1 // ||
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var/const/OOP_AND = OOP_OR + 1 // &&
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var/const/OOP_BIT = OOP_AND + 1 // &, |
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var/const/OOP_EQUAL = OOP_BIT + 1 // ==, !=
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var/const/OOP_COMPARE = OOP_EQUAL + 1 // >, <, >=, <=
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var/const/OOP_ADD = OOP_COMPARE + 1 // +, -
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var/const/OOP_MULTIPLY= OOP_ADD + 1 // *, /, %
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var/const/OOP_POW = OOP_MULTIPLY + 1 // ^
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var/const/OOP_UNARY = OOP_POW + 1 // !
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var/const/OOP_GROUP = OOP_UNARY + 1 // ()
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/*
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Class: node
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*/
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/node/proc/ToString()
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return "[src.type]"
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/*
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Class: identifier
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*/
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/node/identifier
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var/id_name
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/node/identifier/New(id)
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.=..()
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src.id_name=id
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/node/identifier/ToString()
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return id_name
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/*
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Class: expression
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*/
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/node/expression
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/*
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Class: operator
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See <Binary Operators> and <Unary Operators> for subtypes.
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*/
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/node/expression/op
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var/node/expression/exp
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var/tmp/name
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var/tmp/precedence
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/node/expression/op/New()
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.=..()
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if(!src.name) src.name="[src.type]"
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/node/expression/op/ToString()
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return "operator: [name]"
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/*
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Class: FunctionCall
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*/
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/node/expression/FunctionCall
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//Function calls can also be expressions or statements.
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var/func_name
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var/node/identifier/object
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var/list/parameters = list()
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/*
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Class: literal
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*/
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/node/expression/value/literal
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var/value
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/node/expression/value/literal/New(value)
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.=..()
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src.value=value
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/node/expression/value/literal/ToString()
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return src.value
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/*
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Class: variable
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*/
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/node/expression/value/variable
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var/node/object //Either a node/identifier or another node/expression/value/variable which points to the object
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var/node/identifier/id
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/node/expression/value/variable/New(ident)
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.=..()
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id=ident
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if(istext(id))id=new(id)
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/node/expression/value/variable/ToString()
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return src.id.ToString()
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/*
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Class: reference
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*/
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/node/expression/value/reference
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var/datum/value
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/node/expression/value/reference/New(value)
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.=..()
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src.value=value
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/node/expression/value/reference/ToString()
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return "ref: [src.value] ([src.value.type])"
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