edu.mit.csail.sdg.alloy4compiler.ast
Class ExprConstant

java.lang.Object
  edu.mit.csail.sdg.alloy4compiler.ast.Browsable
      edu.mit.csail.sdg.alloy4compiler.ast.Expr
          edu.mit.csail.sdg.alloy4compiler.ast.ExprConstant

public final class ExprConstant
extends Expr

Immutable; represents a constant in the AST.

Nested Class Summary

static class

ExprConstant.Op This class contains all possible constant types.

Field Summary

static Expr	EMPTYNESS The "emptyness" constant.
static Expr	FALSE The "FALSE" boolean value.
static Expr	IDEN The "iden" relation.
static Expr	MAX The largest integer value allowed by the current bitwidth.
static Expr	MIN The smallest integer value allowed by the current bitwidth.
static Expr	NEXT The "next" relation relating each integer to its next larger integer.
int	num If this node is a number constant, then this field stores the number, else this field stores 0.
static Expr	ONE The "1" integer.
ExprConstant.Op	op The type of constant.
java.lang.String	string If this node is a String constant, then this field stores the String, else this field stores "".
static Expr	TRUE The "TRUE" boolean value.
static Expr	ZERO The "0" integer.

Fields inherited from class edu.mit.csail.sdg.alloy4compiler.ast.Expr

ambiguous, closingBracket, errors, mult, pos, weight

Method Summary

int	getDepth() Returns the height of the abstract syntax tree starting from this node.
java.lang.String	getHTML() Returns the description (as HTML) to show for this node.
java.util.List<? extends Browsable>	getSubnodes() Returns a list of subnodes for this node.
boolean	isSame(Expr obj) Returns true if we can determine the two expressions are equivalent; may sometimes return false.
static Expr	makeNUMBER(int n) Constructs the integer "n"
int	num() Return the number if this node is a number constant, otherwise return 0.
Expr	resolve(Type type, java.util.Collection<ErrorWarning> warns) Resolves this expression if ambiguous.
Pos	span() Returns a Pos object representing the entire span of this Expr and all its subexpressions.
void	toString(java.lang.StringBuilder out, int indent) Print a textual description of it and all subnodes to a StringBuilder, with the given level of indentation.

Methods inherited from class edu.mit.csail.sdg.alloy4compiler.ast.Expr

and, any_arrow_lone, any_arrow_one, any_arrow_some, cardinality, cast2int, cast2sigint, closure, comprehensionOver, deNOP, div, domain, equal, equals, findAllFunctions, forAll, forLone, forNo, forOne, forSome, gt, gte, hashCode, hasVar, iff, iminus, implies, in, intersect, iplus, isSeq_arrow_lone, ite, join, lone_arrow_any, lone_arrow_lone, lone_arrow_one, lone_arrow_some, lone, loneOf, loneOf, lt, lte, minus, mul, mult, no, not, one_arrow_any, one_arrow_lone, one_arrow_one, one_arrow_some, one, oneOf, oneOf, or, override, plus, pos, product, range, reflexiveClosure, rem, resolve_as_formula, resolve_as_int, resolve_as_set, setOf, setOf, sha, shl, shr, some_arrow_any, some_arrow_lone, some_arrow_one, some_arrow_some, some, someOf, someOf, sumOver, toString, transpose, type, typecheck_as_formula, typecheck_as_int, typecheck_as_set

Methods inherited from class edu.mit.csail.sdg.alloy4compiler.ast.Browsable

make, make, make, make, showAsTree

Methods inherited from class java.lang.Object

clone, finalize, getClass, notify, notifyAll, wait, wait, wait

Field Detail

op

public final ExprConstant.Op op

The type of constant.

string

public final java.lang.String string

If this node is a String constant, then this field stores the String, else this field stores "".

num

public final int num

If this node is a number constant, then this field stores the number, else this field stores 0.

TRUE

public static final Expr TRUE

The "TRUE" boolean value.

FALSE

public static final Expr FALSE

The "FALSE" boolean value.

IDEN

public static final Expr IDEN

The "iden" relation.

MIN

public static final Expr MIN

The smallest integer value allowed by the current bitwidth.

MAX

public static final Expr MAX

The largest integer value allowed by the current bitwidth.

NEXT

public static final Expr NEXT

The "next" relation relating each integer to its next larger integer.

ZERO

public static final Expr ZERO

The "0" integer.

ONE

public static final Expr ONE

The "1" integer.

EMPTYNESS

public static final Expr EMPTYNESS

The "emptyness" constant.

Method Detail

num

public int num()

Return the number if this node is a number constant, otherwise return 0.

span

public Pos span()

Returns a Pos object representing the entire span of this Expr and all its subexpressions.

Overrides:

span in class Browsable

toString

public void toString(java.lang.StringBuilder out,
                     int indent)

Print a textual description of it and all subnodes to a StringBuilder, with the given level of indentation. (If indent<0, it will be printed in one line without line break)

Specified by:

toString in class Expr

isSame

public boolean isSame(Expr obj)

Returns true if we can determine the two expressions are equivalent; may sometimes return false.

Overrides:

isSame in class Expr

makeNUMBER

public static Expr makeNUMBER(int n)

Constructs the integer "n"

resolve

public Expr resolve(Type type,
                    java.util.Collection<ErrorWarning> warns)

Resolves this expression if ambiguous. (And if t.size()>0, it represents the set of tuples whose presence/absence is relevent to the parent expression) (Note: it's possible for t to be EMPTY, or even ambiguous!)

On success: the return value will be well-typed and unambiguous

On failure: the return value's "errors" list will be nonempty

If we detect any type warnings, we will add the type warnings to the "warnings" collection.

Specified by:

resolve in class Expr

warns - - the list that will receive any warning we generate; can be null if we wish to ignore warnings

getDepth

public int getDepth()

Returns the height of the abstract syntax tree starting from this node.

Specified by:

getDepth in class Expr

getHTML

public java.lang.String getHTML()

Returns the description (as HTML) to show for this node.

Specified by:

getHTML in class Browsable

getSubnodes

public java.util.List<? extends Browsable> getSubnodes()

Returns a list of subnodes for this node.

Specified by:

getSubnodes in class Browsable