# Claro Standard Library: text
# Use: IMPORT "lib/text.claro" AS text
EXPORT ALL

TEACH lower TAKES s
    RETURN LOWER s
LEARNED

TEACH upper TAKES s
    RETURN UPPER s
LEARNED

TEACH trim TAKES s
    RETURN TRIM s
LEARNED

TEACH contains TAKES s, part
    FIND part IN s AS pos
    IF pos = 0
        RETURN NO
    ELSE
        RETURN YES
    ENDIF
LEARNED

TEACH startswith TAKES s, prefix
    FIND prefix IN s AS pos
    IF pos = 1
        RETURN YES
    ELSE
        RETURN NO
    ENDIF
LEARNED

TEACH endswith TAKES s, suffix
    LENGTH s AS ls
    LENGTH suffix AS lp
    IF lp = 0
        RETURN YES
    ENDIF
    IF lp > ls
        RETURN NO
    ENDIF
    SUBSTR s FROM (ls - lp + 1) LEN lp AS tail
    IF tail = suffix
        RETURN YES
    ELSE
        RETURN NO
    ENDIF
LEARNED

TEACH replace TAKES s, old, new
    FIND old IN s AS pos
    IF pos = 0
        RETURN s
    ENDIF
    LENGTH old AS lo
    SUBSTR s FROM 1 LEN (pos - 1) AS left
    SUBSTR s FROM (pos + lo) AS right
    RETURN left + new + right
LEARNED

TEACH split2 TAKES s, sep
    SET out TO LIST
    FIND sep IN s AS pos
    IF pos = 0
        ADD s TO out
        RETURN out
    ENDIF
    LENGTH sep AS ls
    SUBSTR s FROM 1 LEN (pos - 1) AS a
    SUBSTR s FROM (pos + ls) AS b
    ADD a TO out
    ADD b TO out
    RETURN out
LEARNED